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 ::   Intro to Perl 5
 ::   Intro to Perl
 ::   Intro to Perl Taint mode
 ::   Sherlock Holmes and the Case of the Broken CGI Script
 ::   Writing COM Components in Perl

Java tutorials
 ::   Intro to Java
 ::   Cross Browser Java

Misc technical tutorials
 ::   Intro to The Web Application Development Environment
 ::   Introduction to XML
 ::   Intro to Web Design
 ::   Intro to Web Security
 ::   Databases for Web Developers
 ::   UNIX for Web Developers
 ::   Intro to Adobe Photoshop
 ::   Web Programming 101
 ::   Introduction to Microsoft DNA

Misc non-technical tutorials
 ::   Misc Technopreneurship Docs
 ::   What is a Webmaster?
 ::   What is the open source business model?
 ::   Technical writing
 ::   Small and mid-sized businesses on the Web

Offsite tutorials
 ::   ISAPI Perl Primer
 ::   Serving up web server basics
 ::   Introduction to Java (Parts 1 and 2) in Slovak

 

introduction to web programming
Using Libraries  
The next step in your evolution as a CGI programmer is to learn how to customize scripts for your own needs. Thus, the first task is to understand how CGI programs are structured.

Many CGI programs use a common toolbox of routines-called libraries. Thus, it is helpful to understand how libraries work

Web applications are not ferocious. After a bit of delving into the lines of code, you'll often find that a well-written program can be tame.

It's a good idea to view programs as a group of associated algorithms (or routines), all of which have small, well-defined functions. Algorithms are like ants in an ant colony, each doing one small job well.

To decipher a program, you need only focus on understanding how these simple packets of code, called subroutines, interact. With practice, they will call out to you: "I add numbers," "I gather form input," "I parse that input," "I say hello world when asked." If you understand the program one routine at a time, the application's design will emerge and you will be more comfortable modifying and adding to the original program.

There are three types of algorithms that you will be faced with in most Perl CGI applications: individual algorithms, application-specific subroutines, and interapplication libraries. Let's look at each of these types.

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