a-tag

       The a-tag is used to link pages together. Links are the new thing of www, and among other things gave name to one of the first browsers, Lynx. You can also make links internally on a page, e.g. from a table of contents to a chapter.
       Here's an example:

<a href="divex.html">Link 1</a>
<a href="divex.html#links">Link 2</a>
<a href="#links">Link 3</a>
<a name="links" />

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 4 Links and embedded objects - The <a> element
• Diverse opgaver - Links
• Diverse XHTML eksempler - Links
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 1, Introduction to Dreamweaver, Build a page with Dreamweaver, Link the pages

Actionscript

       Actionscript is object oriented, and is like Javascript is other ways too. You can only produce (meaningful) actionscript in the correct environment: flash.

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Kom i gang med Flash MX; Jan -

And/or

       It is possible to check more than one condition at the same time. You just chain them together, with the words "and" and "or". Example:

if ((the hit ship only had one field left)
and (there was only one ship left))
  appoint a winner

if ((this field belongs to player A)
or (this field belongs to player B))
  there shouldn't be water here

Concept last updated: 24/09 2003.

Relationer

Andre kilder

• Eksempler pÃ¥ programmerings-sprog - Og/eller
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 6. Betingede sætninger - Logiske operatorer

Array

       Imagine a shelf for CDs, with little holes for the CDs, enummerated. It is very easy to find no. 22. And there's only space for a finite number of CDs. Arrays work the same way.
       An array is a data type based on the other data types. You can have e.g. an array of numbers or strings. If the data type is numbers, there's numbers in all of the array, etc. Enummeration begins at 0. And you can e.g. address the array myShips, element no. 3 this way:

myShips[3]

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Diverse opgaver - Array
• Eksempler pÃ¥ programmerings-sprog - Array
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 8. Datatabeller

ASP, PHP

       These are 2 examples of scripting languages - i.e. simple programming languages not compiled. They are both good at running at webservers, running serverside. I.e., if I ask what time it is, I'll get the answer from the webserver, not the client. And I can gain access to e.g. a database, that's also on the webserver.
       Both languages are XHTML with embedded program pieces. The program produces more XHTML, and the browser only sees XHTML. In special cases the document doesn't contain/produce any XHTML, but e.g. makes a correction in a database, and then makes sure another page is shown.
       Active Server Page was invented by Microsoft - typically this is VBScript (originates in Visual Basic), embedded in XHTML. There files have .asp as suffix.
       PHP: Hypertext Preprocessor is primarily used on Linux servers, and is free. These files have .php as suffix.
       In very large programs in e.g. javascript, you can easily feel the connection in the program. If e.g. a variable is initiated, it will still be available 5 minutes later. When working with client server, it is easy to end up with a lot of small program pieces, and none of them know the past. To avoid this, you can use sessions, which allow variables to live a long time and be known by different program pieces.

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Active Server Pages; Alf -
• ASP dokumentation -
• Eksempler pÃ¥ programmerings-sprog - ASP, PHP; Session
• Gæstebogen Foxtrot; Alf -
• Lænkede lister -
• php.net -

Bandwidth

       Band width is an expression for how many data can be moved over the network via e.g. a cable within a certain time. E.g. a 56K modem is twice the "width" of a 28K modem. The unit is bps: bits/second. So actually we talk about 28 Kbps or 28,800 bits/second. (Note that when we talk about harddiscs we talk about bytes, and there's 8 bits in a byte. A byte is typically enough for a (small) number or a letter.)
       If the network doesn't have enough band width, TCP/IP packages will be lost, and things will slow down, or not work at all.

Concept last updated: 16/09 2003.

Relationer

Andre kilder

• Grundlæggende brug af Internet i virksomheden; Alf - 2.4 Tekniske problemer pÃ¥ Internet
• Introduktion til den personlige datamat (PC); Alf - Bit, Byte

Branching

       This structure is very like if, but there are more than 2 possible choices. Example:

(fieldColor is defined)
branch on fieldColor
  if "blue"
    write "This is sea"
  if "green"
    write "This is part of a ship"
  if "brown"
    write "Here a ship was hit"
  if "red"
    write "Here some sea was hit"

Concept last updated: 24/09 2003.

Relationer

Andre kilder

• Diverse opgaver - Selektion
• Eksempler pÃ¥ programmerings-sprog - Udgrening
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 6. Betingede sætninger

Browser

       A browser is the piece of software used to display XHTML pages. Different companies and groups of programmers produce different browsers. Through the times some of the big browsers have been Lynx, Mosaic, Netscape Navigator, Internet Explorer (Microsoft), Opera and Mozilla. Apart from the names, they also have versions - a Navigator 2 can't show the same things as a Navigator 4.5 e.g.
       Different browsers show the same content in different ways, if they can get away with it. This is why it's important to find out what browsers the homepage will be shown in, and test the homepage in all of them.
       Since XHTML was chosen as the new standard, browsers were supposed to only show pages following the new standard - but this hasn't happened yet. Many browsers still have a "we guess this is what he meant" principle, when they display pages.

Concept last updated: 25/08 2003.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 1 The web, HTML, and markup languages - Browsers
• Browser Statistics (W3Schools) -
• Diverse opgaver - De 5 dokument-dimensioner + browser
• Grundlæggende brug af Internet i virksomheden; Alf - 3.1 World Wide Web - noget af det

Class diagram

       When the classes have been uncovered and added to the class event table, the classes must be structured.
       There are 4 kinds of structure - the 2 between classes, and the other 2 between objects.
       Generalization: 2 classes are connected in a way so one is a generalization of the other. E.g.: a sub is a ship.
       Cluster: these are classes are connected with either generalization or aggregation (see below), and are collected in a cluster for overview.
       Aggregation: an object consists of other objects. E.g.: the field is part of the gameboard.
       Association: two objects are just connected. E.g.: the gameboard is connected with one player.
       The classes are put together in pairs, and if natural sentences can be made containing the names of both classes, there might also be a structure between them.

Concept last updated: 11/06 2004.

Relationer

Andre kilder

• OOAD slides - 4 Struktur

Class event table

       After the system definition is written, classes and events will be chosen. This includes finding nouns / verbs in the system definition.
       Events are sharply limited events, with a clearly defined before and after: a ship sinks, a die is thrown and so on.
       The tables have classes horizontally and events vertically, and some sort of mark, every time an event and a class have a connection. Examples:
       A player throws a die - therefore the event "throw die" have something to do with the classes "player" and "die".
       A player is created - "create player" has something to do with the class "player".
       Events often develop into methods later.

Concept last updated: 10/06 2004.

Relationer

Andre kilder

• Objektorienteret analyse & design; 3.udgave; Lars Mathiassen, A.M., P.A.N., J.S. (obl. for spil) - kapitel 3
• OOAD slides - 3 klasser

Client/server

       If 2 programs has the relationship, that one program asks the other for a service, we talk about a client and a server. E.g. a webbrowser is a client, when it asks a webserver for a home page. And First Class is a client, when it gets in touch with fc.imma.dk (mailserver) to read email.
       Computers can be connected in other ways than client/server.

Concept last updated: 10/09 2003.

Relationer

Andre kilder

• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 3.3 Udstyr pÃ¥ nettet, 7.1 Internetformater

Component

       The components of a computer are the physical pieces of hardware the computer is built of. This can be: monitor, keyboard, mouse, CD-ROM-drive, floppy drive, harddisc and sound card. A program can be affected by the strength of the expected components - e.g. a program with sounds can be affected by the lack of a sound card.

Concept last updated: 15/09 2003.

Relationer

Andre kilder

• Introduktion til den personlige datamat (PC); Alf - Datamatens opbygning og virkemÃ¥de

Compression

       When files are shrunk, we talk about compression. If you save e.g. a bitmap-picture as gif, you probably have a new smaller file. You save room this way, on your local computer, and on the network if the file needs to be moved.
       With text files, you can use e.g. zip.

Concept last updated: 16/09 2003.

Relationer

Andre kilder

• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 6.2 Grafikformater og farver
• Introduktion til den personlige datamat (PC); Alf - Komprimeringsalgoritmer

Computer

       A computer is a device to receive information (data, in digital form) and manipulate it, to get to a result. The recipe for this manipulation is in a program. Complex computers can also contain data. In this connection a program is also data.

Concept last updated: 10/09 2003.

Relationer

Andre kilder

• Diverse opgaver - Computer
• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 2.1 Datamater
• Introduktion til den personlige datamat (PC); Alf -

Control structure

       If you look through a program, it can seem like one long story. Lines, that are written in a certain order. But they are not always run in the same order as they are written, and some of them may not run at all. We use control structures as one of the mechanisms to control how the program runs. These structures also help programs be smaller and be easier to understand and correct.
       Control structures are grouped together in sequence, selection and iteration. Sequence is the easiest - one line follows the next. Selection is like a choice - do we go left or right? Should we do something or not? "If" and "branching" are both examples of selection. Iteration is, that a piece of program can run 0, 1 or more times, depending on the circumstances. "For" and "while" are examples of iteration.
       When we talk about iteration, we also often talk about loops - a for loop e.g. When it has to be decided e.g. whether a selection should do one thing or another, we do it by examining the circumstances - very often by comparing two numbers or something similar. In this connection it is necessary to have operators to do the comparison - they could e.g. look like this:

== != < > >= <=

if numberOfFields > numberOfHits
  write "This ship is stille here"

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 6. Betingede sætninger, 7. Løkker

Create, alter, drop

       In this category of SQL, we affect the structure of the database, not the content. The first example shows a create sentence, where you typically make a new table. Here's a simple example:

CREATE TABLE player (
    p_name   VARCHAR(50) NOT NULL PRIMARY KEY,
    password VARCHAR(50) NOT NULL
)

ALTER TABLE player
    ADD gender VARCHAR(10)

DROP TABLE player

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• InterBase tutorial mm. (obl.) - s.10-11, s.14-16, s.19-22, s.26-30

CSS

       Cascading Style Sheets is a way to add layout to XHTML pages. The cascading part comes from potentially having more than one style sheet for a single page - and if the same thing is defined more than once, there's a priority deciding which one the browser should choose. Here's an example of a small style sheet.

body {
  font-family: Arial, Helvetica, sans-serif;
  background-color: #808080
}

p.large {
  font-weight: bold;
  font-size: 24pt
}
p#overview {
  font-size: 10pt
}

<p style="color: green">Bla bla</p>

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - bl.a. 3 Getting started - Cascading style sheets
• CSS Colors; W3Schools -
• CSS How To...; W3Schools (obl.) -
• CSS2 Reference; W3Schools (obl.) -
• Diverse opgaver - CSS
• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 6.3 Farvemodeller
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 2, Working with text, Arranging and formatting text, Heads and subheads, Style sheets
• XHTML; Alf - 2.4 Layout pÃ¥ siderne + dele af senere kapitler (2.5.1, 2.5.2B.2)

Database

       We use databases, when it's necessary to update data easily and quickly. E.g. a businessman could be interested in creating a new product in his catalog, meaning the catalog is always updated when it goes to print. Or a webmaster wants the ability to update the news on the front page quickly. Some of the reason a database makes updates like these quick is, that they are well organized.
       When we discuss databases, we normally mean relational databases. This kind of databases was invented in 1970. To make a new relational database, one has to define the tables, rows and columns. With a relational database, it is not necessary to rewrite the whole program, just because a table has a new column - that is some of the reason this type of database gained popularity originally.
       Many companies manufacture databases. IBM manufactures DB2. Oracle manufacture databases, typically knows as Oracle. The same goes for the products of Sybase. Microsoft manufactures e.g. Access (Jet) and SQL Server. Borland manufactures Interbase. MySQL is an open source database, manufactured by MySQL AB.
       A database is just a file - just like a picture, an XHTML document or a Star Office Writer document. An Access file could be named vacation.mdb - an InterBase file could be names horses.gdb - sometimes there's more than one database in the file - sometimes you can't normally see the file in the file system. Just like the other types of files mentioned, there needs to be a program to interpret the contents of the file - for databases this type of program is called DBMS: DataBase Management System. Typically you speak SQL with your DBSM - SQL is a language, developed specially for conversations with databases. DBSM also has another task - to make sure, the database can have multiple simultaneous users. Jet can't do this, so Access databases are not recommended for websites, where we typically hope for many hits. There can be another program on the outside of the DBMS. E.g. Jet has a program called Access, with the purpose of making it possible not to type a lot of SQL, as almost anything can be done graphically. If you write a program in PHP or ASP, connected to a database, you have also made a shell for the DBMS. E.g. somebody wrote a program called phpMyAdmin, which you can install on your webserver, so there's a web interface for the MySQL database, that doesn't normally have a shell.

Concept last updated: 03/07 2003.

Relationer

Andre kilder

• Databaseteori; Alf (obl.) - 1.1.1 og 1.1.2

Development environment

       In an development environment, you can usually do, what you could also do "by hand" - but now you do it through a graphical interface instead. E.g. there are development environments for producing XHTML pages, making it possible to create a home page without knowing XHTML. These tools typically have problems, so you still have to understand the document (even if you can't write it), so you can change the document, removing the worst errors.

Concept last updated: 07/10 2003.

Relationer

Andre kilder

No other sources

Director

       Director is a development environment, that can produce Director movies, later distributed by CD-ROM, DVD-ROM, and networks, including websites. These movies can be complicated programs, or simple presentations of text and pictures.

Concept last updated: 07/10 2003.

Relationer

Andre kilder

• Director 8 - Kompendie I (Intro); Jan -

DNS

       A Domain Name Server knows the connections between IP addresses and domain names. www.imma.dk is a domain name e.g. dk is level 1, imma is level 2 etc.
       Other computers ask DNS's when they don't know the connection themselves. E.g. a request from a browser to www.imma.dk would result in a request to one (or more) DNS(s), returning the IP address - so the browser can continue.
       Some of the level 1 domains are: dk, no, com and edu. This level corresponds to different types of organizations, like countries.

Concept last updated: 16/09 2003.

Relationer

Andre kilder

• Grundlæggende brug af Internet i virksomheden; Alf - 3.1.1 Brugervenlige internetadresser, 3.1.3 Domæner

Documentation

       Documentation is the group of documents manufactured in connection with a certain project/product. A report is documentation e.g. The need for and the volume of documentation varies a lot from project to project. The volume is dependent on how much opportunity there will be to teach the user verbally, among other things.
       Documents can concern themselves with past, present and future. And the same document can concern itself will all 3, depending on the time. The document can design something not made yet, and therefore describe the future. It can also be a todo list for what should be programmed right now. And finally it can be a kind of manual for the finished product, therefore describing the past, what was done.
       Documentation can be aimed at different groups. Some is written for the project group, some for the customer, some for the users, and some for 2 or 3 of these groups.
       Some documentation exists on paper, some electronically. Some forms of documentation are even part of the product.

Concept last updated: 07/08 2003.

Relationer

Andre kilder

• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) -

Dreamweaver

       Dreamweaver is a tool for handling home pages comfortably. You can knit a home page, and within the same program see what it will look like. You can finish the page, and within the same program upload it to the webserver. And when you're an expert in writing XHTML tags etc., you can use the functions in Dreamweaver to produce XHTML, without having to type the tags.
       There are other XHTML tools than Dreamweaver. E.g. Microsoft makes Frontpage. When you want to evaluate how good a tool is, you look for this among other things: what possibilities does this tool offer (do I have to type all the tags myself? - how easy is it to make advanced stuff?), and how nice are the tags (can I read the tags, if the tool produced them? - is it XHTML or HTML?). It's also a paramter whether both beginners and experts can use this tool to their advantage. Using these parameters, Dreamweaver is currently ahead.

Concept last updated: 20/11 2003.

Relationer

Andre kilder

• Diverse opgaver - Dreamweaver + EnSimpelSide.html
• The Web Wizard's Guide to Dreamweaver; James G. Lengel -

E/R-diagram

       The purpose of E/R-diagrams is to give a quick overview of the relevant database. It is important, that all tables are there, but even more important, that all relations are there. In this area tables are called entities, and the system of foreign keys are called relations - entity-relation-diagram. Ideally entities have their own life - postal districts and members have a life of their own, whether they appear in a database or not. Relations are more fluid - they don't always have a real physical existence.
       On the left there's an example of an E/R-diagram. The tables are boxes, and the relations are diamonds, with lines to the tables, there's a relation between. The numbers on the connecting lines show what kind of relation, this is - also called multiplicity. The relation on the right is a one-to-many relation. It is read as: "one player can write many messages". The relation on the left is a many-to-many relation - one player can be in many chatrooms, and a chatroom can contain many players. It's also possible to have a one-to-one relation. You don't reach this relation by normalization, but can choose it for optimization. E.g. a table can have columns often used (name and password is used at every login), and other columns almost never used (a users gender and birthday). In this case the table can be split, so the columns often used are apart.
       A special kind of E/R-diagram is called Bachman-diagram. As many-to-many relations become new tables, it's not allowed to have many-to-many relations in Bachman-diagrams - they must also be shown as tables. So this kind of diagram is a bit closer to showing the real look of the database.
       E/R-diagrams can be more slim than shown here. Names of columns and relations don't have to be here. But names of tables and multiplicity should always appear.

Concept last updated: 07/07 2003.

Relationer

Andre kilder

• Databaser; Teori og praksis; 2.udgave; Lars Frank; 1.3.2, Bachman diagrammet (s.29-30) -
• Databaseteori; Alf (obl.) - 1.2 - E/R-diagrammer frem til Referentiel integritet
• Diverse opgaver - E/R-diagram

EnSimpelSide.html

       This is an example of a simple XHTML page. Here's the simple code.

<?xml version="1.0" encoding="ISO-8859-1" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
	"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>A simple page</title>
</head>
<body>
<p>Lises nice simple page</p>
</body>
</html>

Concept last updated: 12/09 2003.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 3 Getting started
• Diverse opgaver - Dreamweaver + EnSimpelSide.html
• EnSimpelSide.html -
• EnSimpelSide.xml -
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 1, Introduction to Dreamweaver
• XHTML; Alf - 2.1 Sidens indhold + 2.2 Forklaring pÃ¥ koden

Event

       A running program can wait for certain events. E.g. a browser can show a page, built up with the javascript event handlers mouseover and mouseout. So the browser has to look for the mouse visiting certain areas - and when the event occurs, a certain piece of program will be run.

Concept last updated: 15/09 2003.

Relationer

Andre kilder

• Diverse opgaver - Events
• Gæt et bogstav -
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 5. Hændelser

Exploring development

       Exploring development has this name because the goal isn't set at the beginning - so you have to explore the "landscape". This is solved as the phase where the product is designed, programmed and tested is run through several times, until you're done and the product is "large enough". It's an asset that a program can be written, even though nobody knows beforehand how to do it - but it's a disadvantage, that the program might not be as efficient. A typical error is to write a piece of program, that in the end isn't used, but is still run.

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) - s.29-39

File system

       A file is a bunch of data, that can be moved together. E.g. an XHTML document, a gif picture or an Interbase database. Further it has a name, unique in that particular directory. The name can have a suffix (a last syllable - in this case what's after the dot), e.g. gif or html .
       A directory is sort of a drawer, where you can put files and other directories. Directories also have names, that also need to be unique.
       Here's a couple of examples of paths - in this case absolute paths:

C:\lisea\game\ship.gif
D:\backup\20030910.zip
D:\old\backup.txt
/usr/local/apache/bin/httpd

..\old\backup.txt

/usr/local/home/lisea/public_html/lise.html
/~lisea/lise.html

Concept last updated: 10/02 2005.

Relationer

Andre kilder

• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 4.4 Styresystemer

Firewall

       A firewall is a kind of valve: it's easy to get out (on the internet), but hard to get in.
       The firewall is one or more programs on a computer, that's also a node between intranet and internet. All packages going through are checked. Some of the packages are discarded. A typical rule for checking is to check which porst are allowed.
       A rule of thumb: a firewall starts as closed, and has to be opened to allow the necessary access.

Concept last updated: 15/09 2003.

Relationer

Andre kilder

• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 9. Virksomhedens sikkerhedsstrategi og -politik
• \\2000\diverse\Lise\goodwarriors.mpeg -

Flash

       This is a development environment, that is very good at producing vector graphics animation programs.

Concept last updated: 07/10 2003.

Relationer

Andre kilder

• Kom i gang med Flash MX; Jan -

Flowchart

       The flowchart documents the interaction design - the organization of data, and the most importaint routes through data. It is less detailed than a navigation diagram. The example on the left documents, that I will have 2 blocks and a front page. One block describes the rules of the game. The other gives options of playing and chatting. Each block could end up as more than one screen. The blocks are the blocks that were defined in the information design - i.e., what data does the product contain, and how should they be structured. I have e.g. decided, that choosing an opponent and the game itself, and the chat alongside the game, all should be in one block.

Concept last updated: 10/08 2003.

Relationer

Andre kilder

• Interaktionsdesign -
• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) - 5. Designtrinnet; Opbygningen af flowcharts (s.129-130)

For

       This kind of loop is good for program pieces meant to run (almost) the same way many times. Here's an example:

for the numbers 1-5
  draw myShips[number]

Concept last updated: 23/09 2003.

Relationer

Andre kilder

• Diverse opgaver - Iteration
• Eksempler pÃ¥ programmerings-sprog - For
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 7. Løkker - for-løkker

form-tag

       You can make formulas in XHTML - a collection of fields and menues, so users can type in their information, and send it to the webserver, that might then produce e.g. an email, or put it in a database.
       The most important tag in this connection is form, surrounding all of the formula. form takes a number of attributes. One of them is action - here you write the name and place of the script, that's supposed to get data from the formula. Another one is method, showing how the data should be sent. If you choose get, you will later see data as part of the URL, at the top of the browser. If you choose post, data is sent in another way. Post makes it possible to send more data, and is safer, so normally it is preferred in formulas.
       Inside the formula, the most important tag is input, making type in fields, buttons etc. possible. input takes among other things the attribute type, that might have the values text (ordinary text), password (like text, but on the screen the typed will be shows as stars), hidden (also text, but the value won't be shown on the screen), submit (a button, that sends the data), image (also a button, but here a picture can be used), checkbox and radio (two different ways to make fields, that accept clicks).
       There are also other tags for use in formulas. select is a tag, that can surround one or more option tags. The result is a menu, one line for every option.
       An example.

<form action="http://stream.imma.dk/lisea/bog/dok/visalt.php"
method="POST" name="creation" onSubmit="return afsendelse(this)">
<input type="hidden" name="secret" value="A secret field" />
Name: <input type="text" name="navn" /><br />
Type: <select name="type">
<option>Player</option>
<option>Administrator</option>
</select><br />
<input type="submit" />
</form>

Concept last updated: 15/04 2004.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 15 XHTML forms
• Diverse XHTML eksempler - Formularer
• Eksempler pÃ¥ programmerings-sprog - Formular
• Start pÃ¥ Javascript 1.2, eksemplerne - 5.8, bil-valg
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 5, Working with forms

frame-tag

       With frames the browser window can be split into several smaller windows, all containing XHTML documents. An example:

<frameset cols="30%,55%,15%">
  <frame src="menu.html">
  <frame src="main.php">
  <frame src="fun.html">
</frameset>

Concept last updated: 07/10 2003.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 7 Frames
• Frame-eksempel -
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 6, Formatting pages, Frames

FTP

       File Transfer Protocol makes it possible for files to be copied between machines. There are special clients, who can only do FTP, but Dreamweaver also has FTP functionality built in. So you can e.g. copy an XHTML document from your own computer to a webserver with FTP.
       We talk about upload/put and download/get. In Dreamweaver put is symbolized by an arrow pointing up, and get by an arrow pointing down. So in this sense the internet is "up". We put stuff up on the internet, or pull it down from the 'net.

Concept last updated: 10/09 2003.

Relationer

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• Grundlæggende brug af Internet i virksomheden; Alf - 3 Tjenester pÃ¥ Internet

Function

       This is a small piece of program, nicely packaged, and put slightly away. Furthermore, this piece won't run unless it is called.
       Functions make easy recycling (the function can be called several times from different places), quick fixes (only one place to change the program), and quick change overs (a whole function can be replaced by another).
       Here's an example:

function shootAtShip(x,y)
  if there's a ship at (x,y)
    mark this ship as hit in (x,y)
    return 1
  else
    return 0

Concept last updated: 24/09 2003.

Relationer

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• Diverse opgaver - Funktioner
• Eksempler pÃ¥ programmerings-sprog - Funktion
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 4. Funktioner

Good programming

       This is a disciplin, that makes programs easy to read and correct, and work better. It contains several items.
       Comments in the program can describe what the program should do. You can choose to have a comment for 100 lines ("Below the database and its 7 tables are updated."), or for every line ("Make connection to the relevant database."), or something in between.
       Space (tabulation, space and line breaks) can arrange the program in different ways, to make it easier to read - like we bend other kinds of text to make it more readable.
       Platform independency - that the program works on all computers (including software), that you might imagine - also computers with old and unusual software.
       Error checking - often the file system, databases etc. are used, and these don't always cooperate. In nice programming you know this, so the user can get a nice error message (i.e. one I have written), instead of something more or less understandable from the program.
       Functions.
       No superflous code - if you have worked with a program for a long time, there are often bits and pieces all over the place no longer in use, only there to confuse. It's okay to have a phase to remove extra code. If you use a development environment, there might also be extra code, that has to be removed by hand.
       Good names - both variables and functions can be named by the programmer, and should have good names. A counter might be named i, e.g. if it's only alive for 4 lines, in a for loop. Another variable might be called noErrors, and live for many lines. It's easier to remember what the variable contains, when you bump into it. And it should contain the number of errors, and not the width of the browser!
       Normalization, referential integrity etc. - or in other words, the tools that support and optimize the use of databases.
       Nothing hard coded - sometimes you write something directly in a program, when the correct procedure would be to get it from a table in a database or something similar. It's actually redundancy to have it in two places. This is called hard coding. And it's not nice.
       Works with low bandwidth - this is achieved by having javascript checks on formulas, compression of pictures etc.

Concept last updated: 06/05 2004.

Relationer

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• Eksempler pÃ¥ programmerings-sprog - Kommentarer, Funktion

HOME

       HOME (Holistic Open Multimedia development mEthod) is a tool box of phases, documents etc. There are also 3 methods, picking different things from the tool box, but you can also construct your own. It's a bit like knitting. HOME is like having learned how to cast on and how to do knit and purl. But you need more. If you choose a method (e.g. prototyping) you also have a pattern - that says you should cast on 47 meshes and knit 50 rows, to knit a sweater. HOME is not a system development method by itself.

Concept last updated: 11/07 2003.

Relationer

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• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) -

HTTP

       The service World Wide Web (www) uses the protocol HTTP - HyperText Transfer Protocol.
       Typically you see the protocol in use when a new URL (Uniform Ressource Locator) is called in a browser. Below you see an example of a URL.

http://www.ships.com/battleships/start.html

Concept last updated: 10/09 2003.

Relationer

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• Grundlæggende brug af Internet i virksomheden; Alf - 3 Tjenester pÃ¥ Internet
• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 7.1 Internetformater

If

       If sentences lets me examine one or more circumstances, and then acting in different way, depending on whether the circumstances fullfill some needs or not. An example:

(somebody fired at (x,y))
if there's a ship on (x,y)
  decrease the number of fields in this ship by 1
  write "Smack!"
else
  write "Plop"

Concept last updated: 24/09 2003.

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• Diverse opgaver - Selektion
• Eksempler pÃ¥ programmerings-sprog - If
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) - 6. Betingede sætninger

Image format

       Images can be in many formats. Let's start with the easy way to make a picture. 200 pixels horizontally and vertically means 40,000 points in all. And if it's good, there's one byte for each of the colors red, green and blue, to make "every" color (16,777,216 in all). 3 bytes are 24 bits. So we need 40,000 x 24 bits. Bitmaps (.bmp) are made like this, and result in big files.
       gif is another format. There's only one byte for the colors, therefore only 256 colors to choose from. So now there's 40,000 x 8 bits. We also need some room to keep track of which 256 colors are actually used - depending on e.g. whether the picture is very green or very red. The picture can also save some room by saying "this pixel is green, and so are the next 77".
       jpg is yet another format. Where gif is good at drawings with lines, because this results in long lines of pixels, jpg is compressed in another way, good for photos.
       Other possible formats include tif and png.

Concept last updated: 06/05 2004.

Relationer

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 6.2 Grafikformater og farver

img-tag

       This tag is used to add pictures. The most important attribute is src, showing the name and place of the picture. Example:

<img src="ship.gif" />

Concept last updated: 09/10 2003.

Relationer

Andre kilder

• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 5 Images
• Diverse opgaver - Billeder
• Diverse XHTML eksempler - Billeder
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 3, Working with images

Insert, update, delete

       In this category of SQL we change the content of the database. The first example is to insert a new row in a table. Here's a simple example.

INSERT INTO player
(p_name, password, gender)
VALUES
('jean','carrot35','man')

UPDATE  player
SET     password = 'horse56'
WHERE   p_name = 'jean'

DELETE FROM     player
WHERE           p_name = "jean"

Concept last updated: 06/05 2004.

Relationer

Andre kilder

• InterBase tutorial mm. (obl.) - s.31-36

Javascript

       Javascript was constructed to make small programs in XHTML documents. This also means it's a client side language - it runs on the client (the users PC), not on the webserver. Here's a small example:

<script language=JavaScript>
  <!-- // Hides the script from older browsers

  document.write("Hello world!")
  
  // End of comment hiding the script from older browsers -->
</script>

<script language=JavaScript>
  <!-- // Hides the script from older browsers
  document.write("<table border='1'>")
  for (i=1; i<11; i++) {
    document.write("<tr>")
    for (j=1; j<11; j++) {
      document.write("<td align='right'>" + i*j + "</td>")
    }
    document.write("</tr>")
  }
  document.write("</table>")
  // End of comment hiding the script from older browsers -->
</script>

Concept last updated: 25/08 2003.

Relationer

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• Beginning XHTML; Frank Boumphrey, CG, DR, JR, SS, TW - 16 Javascript
• DevGuru JavaScript Index -
• Diverse Javascript eksempler -
• Diverse opgaver - Mouseover
• Eksempler pÃ¥ programmerings-sprog - Javascript
• Javascript tutorial, W3Schools (obl.) -
• Start pÃ¥ Javascript 1.2, eksemplerne -
• Start pÃ¥ Javascript 1.2; Tom Negrino og Dori Smith; IDG -
• Start pÃ¥ Javascript 1.5; eksemplerne (obl.) -
• Start pÃ¥ Javascript 1.5; Jes Nyhus; 1.udgave (obl.) -
• XHTML; Alf - 2.5.2A Javascript

Language of formatting

       A language of formatting is a primitive programming language. The task to be solved is not very dynamic, but just is about formatting some content. Formatting can be many things: saying that the picture should be on the right, that the text in this paragraph should be with larger letters etc. It can also be to say, that this piece of text is the title of a book, while this other piece is an overview. Typically you can do the same things as you can in Microsoft Office Word and Star Office Writer.

Concept last updated: 06/05 2004.

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Layers in XHTML

       Previously you could only control the exact placement of pictures and images with tables - and it didn't work that well. Later we got layers, that in some ways work better. Among other things layers can overlap, so I can place some text over a picture.
       There are two tags for layers. <div> is a block element (so you can't have more divs inside each other), and <span> is an inline-element.
       divs and spans can be used to let things overlap, and to give very precise positions, but they can also be used more peacefully to come one after the other. Here's a small example.

<div style="background-color: green">
<span style="position: relative; left: 7px; top: 15px;
height: 97px; width: 100px; background-color: red; z-index=2">
Hi mum
</span>
<span style="position: relative; left: -37px; top: 5px;
height: 7px; width: 100px; background-color: yellow; z-index=1">
Hi grannie
</span>
</div>

Concept last updated: 28/08 2003.

Relationer

Andre kilder

• Diverse XHTML eksempler - Lag
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 6, Formatting pages, Layers
• XHTML; Alf - 2.5.1 XHTML kodernes attributter; 2.5.2B Et mere avanceret eksempel

Library

       This is typically a collection of functions in a separate file, which can then be included from other files.

Concept last updated: 23/09 2003.

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• Eksempler pÃ¥ programmerings-sprog - Bibliotek

LINGO

       LINGO is the language Director contains, and which you can choose for programming, for more advanced functions.

Concept last updated: 07/10 2003.

Relationer

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• Director 8 - Kompendie I (Intro); Jan -

Navigation diagram

       The purpose of a navigation diagram is to illustrate the navigation on a home page e.g. The individual pages are boxes, with the file name. There's an arrow from one box to another if there's a link from one to the other - so, in this example, there's a link on the page index.html to rules.html.
       You can also illustrate contact to a database - in this case newgame.asp contacts a database, before producing the ready page, shown in the browser.
       As with all other kinds of documentation, it should be considered whether a navigation diagram actually makes things clearer. With a very complex diagram, it might be better to have more than one diagram, and then loosely show, what their connection is. In some cases, there are things hard to illustrate - e.g. frames. Some things are easier to write in text - e.g. "and all pages link back to index.html".

Concept last updated: 08/08 2003.

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Network

       The best known example of a network is probably the internet. But there's also an intranet (a small network, where a firewall closes down for access from the outside) and an extranet (here you can get inside from the outside - First Class is sort of an extranet). The phone net is also a network btw., and some places the phone net is the basis for the internet.
       Physically a network is built of nodes (machines) and communication ways (wires).
       Network makes other services possible. One of them is email. Another one is news - these can be read by Google, in their fan for Groups, but there's also a special client and protocol for this.

Concept last updated: 10/09 2003.

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• Det store netværksspil -
• Grundlæggende brug af Internet i virksomheden; Alf - 2 Hvad er Internet?
• Warriors of the net (obl.) -
• \\2000\diverse\Lise\goodwarriors.mpeg -

Normalization

       The purpose of normalization is to avoid redundancy and inconsistency. Redundancy is the phenomenon, that I repeat myself - it's relations that I don't want to repeat. If e.g. I want to save in my database, that the player named Jean is a man, it would be practical to only save it one place. If I have a giant table, keeping track of all players, chat rooms and so on, I probably have to write more than once, that Jean is a man. This is redundancy, and I want to avoid it. Inconsistency is the phenomenon, that I try to repeat myself, but don't succeed. Maybe I made a typo, and somewhere it says, that Jean is a woman.
       Another problem connected to not having a normalized database is, that I might delete data, I wanted to save. If Jean isn't chatting anymore, I might delete his password and gender. And that's not fair, just because the man doesn't want to chat 24/7.
       Before I begin normalizing, I need some concepts in place. A primary key is a column, where all the values are unique, and where every value somehoe corresponds to the whole row. A phone company would probably have a table, where the primary key is the phone number. CPR (Central Person Register) probably has a table with CPR-numbers as a primary key. A primary key can also be more than one column - then it's a composite primary key. E.g. a table to keep track of which players chat in which rooms, would have a primary key composed of the IDs for players and chat rooms. Later when we cut tables up, there will typically also be a foreign key. E.g. the table with the composite key above, will also have a foreign key to the player table. With a foreign key we can also accomplish something else: referentiel integrity. If I have a table with all the registrered players, I can make sure, that there isn't suddenly a non existant player chatting.
       And then there's the normalization itself - see the rules elsewhere.
       Once I'm this far, the next step is to write a data dictionary. Here I register the name of every table, and for every table the name of every column. Apart from the name, I register the data type, whether the field might be empty and whether it's a primary and/or foreign key. The datatype can be integer, string, date and so on. An interesting datatype is autonumber, where the database makes sure, every row created gets the next number.

Concept last updated: 06/05 2004.

Relationer

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• Databaseteori; Alf (obl.) - 1.2
• Normalisering, eksempler (obl.) - Dataordbog

OOAD

       OOAD (Object Oriented Analysis and Design) is a system development method with a few basic principles.
       One of them is, that the socalled objects should be close to reality: in our game we have a player, a board, a ship etc., and in a physical game they would all have a physical existence, identity, state and behavior. (There can be other objects, but they are added later.)
       Obejcts that are related, are structured in classes. Another principle is, that a class in the program should appear close to its attributes (variables) and methods (functions). It should also be easy to make sure, that the attributes can be changed only through the methods - no direct touching. A good class can be recycled in other programs.
       Another principle is, that things survive a long time. You might write down the names of the first classes after the first meeting with the customer, and 2 years later these names are still in the finished program. This also means documentation of other kinds have a long life.
       OOAD focuses on objects and data, where older methods focused on actions and logix. It was a revolutionizing way of looking at the world, as it appeared.

Concept last updated: 07/08 2003.

Relationer

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• Kode til OOAD eksempel, ASP -
• Kode til OOAD eksempel, PHP -
• Objektorienteret analyse & design; 3.udgave; Lars Mathiassen, A.M., P.A.N., J.S. (obl. for spil) - kapitel 1
• OOAD slides -

Operating system

       3 wide spread operating systems are Windows, Mac OS X and Linux.
       An operating system is the lowest level on a computer. It controls/handles the other programs. It opens the possibility, that more programs can run at once.

Concept last updated: 15/09 2003.

Relationer

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 4.4 Styresystemer

Patch

       A patch really is a patch - something used to correct an error in a program, without me having to install a whole new version of the program.
       The advantage to correcting errors is, that security goes up. Some errors are used to tumble programs, so they can't do their security job.

Concept last updated: 15/09 2003.

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Pattern of behavior

       When the first class diagram is ready, it's time to describe attributes for the classes and make patterns of behavior.
       You can describe a chain of events for a single object. These can be very different, e.g. because objects of the same class can have very different lifespans - some players play every day for a year, others just come once, and are then removed from the system.
       After the event chains have been explored a pattern of behavior can be made, describing all possible chains of events. The example on the left describes the different things a field might experience - e.g. that it might have a ship or not, and that it might be hit or not.
       As the classes get patterns of behavior, the attributes are also noted. I note e.g., that for a field I need to know, whehter it has a ship, and whether it's been hit.

Concept last updated: 15/06 2004.

Relationer

Andre kilder

• OOAD slides - 5 Adfærd

Platform

       A computer system, where a program can run. I might write a battleships program, meant to be installed on a Windows PC - so now I'm writing for the platform Windows. Similarly I can write a program, using javascript, tested in Internet Explorer - now I'm writing to the platform IE.
       Some programs exist on most platforms, so programs written in these languages are platform independent. Some home pages are carefully written, so they look the same in all browsers, thereby being platform independent.

Concept last updated: 15/09 2003.

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Port

       The same computer can have several programs related to the network. Therefore they get one or more ports each. This is used e.g. when another computer wants to talk to a certain program, and then asks for the relevant port.
       The ports are simply numbers, between 0 and 65536. 0-1024 are special. HTTP typically uses port 80, FTP uses port 21, and email (SMTP) port 25.

Concept last updated: 15/09 2003.

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• \\2000\diverse\Lise\goodwarriors.mpeg -

Process

       A running program is also called a process. In some cases a program can become more processes - e.g. one process for every user.

Concept last updated: 15/09 2003.

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Processor

       A processor is a central piece of hardware, very good at logic and handling the simplest language, the computer speaks. On top of this are built other languages, until we reach e.g. ASP and PHP. The processor controls the running of the program, on its level.

Concept last updated: 16/09 2003.

Relationer

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 2.1 Datamater
• Introduktion til den personlige datamat (PC); Alf - Styreenheden

Program / application

       Programs have behavior (behave differently in different situations) and can make static (unchangeable) thing dynamic (changeable).
       So what is a computer program? 1. A plan or routine, that can solve a given problem on a computer. 2. A number of instructions (program elements) that a computer needs, to do a given job or solve a given problem.

Concept last updated: 15/09 2003.

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• Diverse opgaver - Begrebskort 3

Program element

       If you read a lot of programs closely, you'll see a lot of words and structures repeatedly, and they mean the same every time. In this connection they are called program elements. Program elements may look different in different languages, but typically work the same way everywhere, so you just have to figure out how they look in the language in question.

Concept last updated: 24/09 2003.

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• Eksempler pÃ¥ programmerings-sprog - VilkÃ¥rligt program-element

Programming language

       A programming language is characterized by: you can write program with it. There are many different programming languages and types of programming languages, there are good at different things. Some are good at running fast, others are fast to program. Some are good for web use, others run best on a PC.
       Originally programming languages were based on the concept, that we let machines do arithmetic, instead of us doing it ourselves. But later we have become very good at making anything into arithmetic, so computers can do it for us.
       A definition of what a programming language is could be: an artificial language, used when you want to write computer programs.

Concept last updated: 22/08 2003.

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• Eksempler pÃ¥ programmerings-sprog - Hello world

Protocol

       A protocol is a set of rules for communication.
       In the real world we have a protocol for how people communicate with mail - a mail protocol. You write a letter, throw it in the mail box, the postal service will sort and transport, a mailman delivers, and at the other end the letter is read. An answer is made the same way.

Concept last updated: 10/09 2003.

Relationer

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 3.4 Det fysiske net, ledninger og netkort

Prototyping

       Prototyping is characterized by, that part of the phase of analysis is to make and test prototypes, and then throw them away. This does, that analysis ends with a clear goal - a goal that wasn't clear from the beginning. The goal is less clear than with the waterfall method, but more clear than with exploring development.

Concept last updated: 11/07 2003.

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• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) - s.29-39

Proxy

       A proxy acts on behalf of somebody else - in this case a browser has asked for a document from the internet and the proxy goes and gets it. The illustration shows, that the document comes back through the internet, through the proxy (saving a temporary copy) and out to the client.

Concept last updated: 16/09 2003.

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• \\2000\diverse\Lise\goodwarriors.mpeg -

Pseudo language

       As there are many kinds of programming languages, but not quite as many ways to write programs, you can also write programs in pseudo language. The program doesn't have to look like any language in particular, and you can just write plain English for what the program is supposed to do. If you write the program in pseudo language first, change this into comments, and then add the real program later, this can make overview easier.

Concept last updated: 24/09 2003.

Relationer

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• Eksempler pÃ¥ programmerings-sprog - Pseudokode

RAM

       Random Access Memory is the old name for this type of memory - and the name isn't that well chosen anymore. RAM is faster than other kinds of memory, but also relatively small (RAM can be e.g. 256 MB, and a harddisc might be e.g. 40 GB - 160 times more). Therefore RAM quickly fills up, and then there's a strategy for how data are thrown away, to make space for the new, that's needed right now.
       RAM is used for a temporary copy of operating system, programs and data, so the processor can reach them fast. When the computer is turned off, the RAM is emptied. RAM is often the bottleneck on a computer, especially if there's too little RAM, and the computer is moving data to the RAM all the time (swapping).

Concept last updated: 16/09 2003.

Relationer

Andre kilder

• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 2.1 Datamater
• Introduktion til den personlige datamat (PC); Alf - RAM

Router

       The job of a router is to sit in a node between 2 networks, and deciding where the packages should go. It might also throw away packages, after laid down rules. A rule of thumb: a router is open, and has to be closed to give more security.

Concept last updated: 16/09 2003.

Relationer

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 3.4 Det fysiske net, ledninger og netkort
• \\2000\diverse\Lise\goodwarriors.mpeg -

Schedule

       A schedule answers many of the questions, that goes into organizing a larger job: who does what when and for how long - the last one is tough, and can only be learned from practice. The schedule also organizes the deadline.
       Curt, 14 hours, database design, after October 15, finished by November 1.
       Curt, 5 hours, write test plan, after October 25, finished by November 5.
       Peter, 5 hours, write test plan, after October 25, finished by November 5.
       Etc.
       A good supplement for a schedule is the action of registering time, where you note as accurately as possible the time for an activity, and who did it when. This makes it possible to go back and check up on the quality of the time estimates (guesses), as the schedule was made - and that makes the estimates better next time.
       A time register should be as accurate as the schedule. It's fair to count hours.
       Wednesday, Curt, 3 hours, database design.
       Thursday, Curt, 4 hours, database design.
       Thursday, Curt, 2 hours, write test plan.
       Thursday, Peter, 1 hour, write test plan.
       Etc.

Concept last updated: 08/08 2003.

Relationer

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• Udvikling af multimedier - en helhedsorienteret metode; 1.udg.; Marie Chr., L.H.F. (obl., ikke-spil) - s.58-60

Security

       The purpose of security is to protect IT values / data. There are many different strategies to increase security, e.g.:
       To demand username/password from users.
       Taking backup - i.e., make a copy of data. If data is deleted later, the old copy can be read.
       Encryption. Here data is "translated" to languages, that are very hard to understand for outsiders.
       Proxy, router and firewall work closely together to regulate the contact between the local network and the internet.
       A threat to security is virus - small programs, copying themselves between machines, typically to destroy the machine. You can use anti-virus-programs and elementary knowledge of viruses against this - like, don't run random programs in emails.

Concept last updated: 15/09 2003.

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• Informationsteknologi B til HH; 1.udgave; Peter Zangenberg, JPJ, FDM (obl.) - 9. Virksomhedens sikkerhedsstrategi og -politik

Select

       This is a category of SQL, where we look at the database, to see what it contains. Here's a simple example of that kind of SQL.

SELECT  p_name
FROM    player

SELECT  p_name,
        gender,
        text
FROM    player,
        message
WHERE   player.p_name = message.p_name

Concept last updated: 18/05 2004.

Relationer

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• InterBase tutorial mm. (obl.) - s.37-62

Shockwave

       A flash program / a shockwave file as a package (compiled) is small enough to work on www. The files have .swf as suffix. These files can be embedded in XHTML pages, or called directly from a browser.
       A compiled file can't be opened, so the program can't be read, and the program runs faster.

Concept last updated: 06/05 2004.

Relationer

Andre kilder

No other sources

Sound and video in XHTML

       It's possible to make sound and video files in other programs: .wav, .mp3, .mid, .mov, .mpg, .swf and so on. These can also be included in XHTML documents, like pictures, although you typically need a bit more work on the tags to make it work - like mentioning which plugin to use. Below is an example of how to include a sound file in wave format.

<embed SRC="snd/Desol18a.wav" WIDTH="300" HEIGHT="100" 
PALETTE="foreground" />

Concept last updated: 28/08 2003.

Relationer

Andre kilder

• Et flash eksempel -
• Musik; Alf -
• Plugins; Alf -
• Streaming; Alf -
• The Web Wizard's Guide to Dreamweaver; James G. Lengel - Chapter 4, Working with multimedia

Specification

       Depending on what method is used, a specification can have many names. It can be called e.g. product definition, concept description and system definition. It is an attempt to describe the goal of the project.
       It can answer many questions - typically there's a lot of attention to functionality, but there might also be focus on: what's the target group, what is the purpose, who's the customer, what technology will be used, how will the product be used, what about maintenance, does the project have a name, what is the idea of the project, what are the contents, what is the shape...

<h3>A headline</h3>

<ul>
<li>The first line</li>
<li>The second line</li>
</ul>

	<table border="1"><tr><td>
Field 1
	</td><td rowspan="2">
Field 2
	</td></tr><tr><td>
Field 3
	</td></tr><tr><td colspan="2">
This is a table.
	</td></tr></table>

<table border="1">
	<tr>
		<td>Field 1</td>
		<td rowspan="2">Field 2</td>
	</tr>
	<tr>
		<td>Field 3</td>
	</tr>
	<tr>
		<td colspan="2">This is a table.</td>
	</tr>
</table>

area = length * width
if ( area > 50)
  demand much money

as long as there's 1 ship left
  shoot at the ships

<img src="ship.gif" border="0" />

-- <?xml ?> -- <!DOCTYPE !> -- [html] --

[html]: -- <html> -- [head] -+- [body] -----+- </html> --
                             +- [frameset] -+

[head]: -- <head> -- <title>bla</title> -+------------+- </head> --
                                         +- <link /> -+
                                         +- - - - - --+

[body]: -- <body> ---+-----------+-+- </body> --
                   ^ +- [block] -+ |
                   +---------------+

[frameset]: -- <frameset> ---+- <frame /> --+-+- </frameset> --
                           ^ +- [frameset] -+ |
                           +------------------+

[block]: --+- <h1>bla</h1> -+--
           +- <h2>bla</h2> -+
           +- - - - - - - --+
           +- <h6>bla</h6> -+
           +- [p] ----------+
           +- [table] ------+
           +- [list] -------+
           +- <hr /> -------+
           +- - - - - - - --+

[inline]: --+- <em>bla</em> ---------+--
            +- <strong>bla</strong> -+
            +- <img /> --------------+
            +- <a>bla</a> -----------+
            +- - - - - - - - - - - --+

[p]: -- <p> ---+- bla ------+-+- </p> --
             ^ +- [inline] -+ |
             +----------------+

[list]: --+- <ul> -+--- <li>bla</li> -+-+- </ul> -+--
          +- <ol> -+ ^                | +- </ol> -+
                     +----------------+

[table]: -- <table> --- <tr> --- <td>bla</td> -+- </tr> -+- </table> --
                     ^        ^                |         |
                     |        +----------------+         |
                     +-----------------------------------+

<table>
  <tr>
    <td>
    Some content
    </td>
  </tr>
</table>

<p>Some content.</p>

<br />

<img src="myShip.gif">

<?xml version="1.0"?>

<ship name="Georg Stage" fields="3">
<start x="4" y="3" />
<end x="4" y="5" />
<hit field="2" />
</ship>