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

Java tutorials
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Misc technical tutorials
 ::   Intro to The Web Application Development Environment
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 ::   Intro to Web Design
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 ::   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 scalar variables  
The benefit of substituting a scalar variable name for a value is that we can then manipulate its value. For example, you can "auto-increment" a scalar variable using the "++" operator:

    $number = 1;
    print "$number\n";
    $number++;
    print "$number\n";

Perl would send the following to standard output

    1
    2

You can also perform arithmetic such as:

    $item_subtotal = $item_price * $quantity;
    $shipping_price = 39.99 * $quantity;
    $grand_total = $item_subtotal +
    $shipping_price;

Scalar variables are the meat and potatoes of CGI. After all, translating between the client and the Web server is essentially the formatting and the reformatting of variables. Be prepared to see them used a lot.

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