Apache is the most popular web server on the Internet because it is free, reliable, and extensible. The availability of the source code and the modular design of Apache makes it possible to extend web server functionality through the Apache API. For the most part, however, the Apache API has only been available to C programmers, and requires rebuilding the Apache server from source. mod_perl, the popular Apache module used primarily for enhanced CGI performance, changed all that by making the Apache API available to Perl programmers. With mod_perl, it becomes simple to develop Apache modules with Perl and install them without having to rebuild the web server..