The Comprehensive Perl Archive Network (CPAN) is a large repository of software and documentation for the Perl programming language. It contains thousands of modules and distributions that extend the functionality of Perl, making it easier for developers to find and use pre-written code for various tasks. CPAN is organized into a structured directory system, allowing users to search for modules by name, category, or author. It also provides tools for installing and managing these modules, streamlining the development process for Perl programmers and fostering a collaborative community around the language.