The CPAN module automates or at least simplifies the make and install of perl modules and extensions. It includes some primitive searching capabilities and knows how to use Net::FTP or LWP or some external download clients to fetch the distributions from the net.
These are fetched from one or more of the mirrored CPAN (Comprehensive Perl Archive Network) sites and unpacked in a dedicated directory.
The CPAN module also supports the concept of named and versioned bundles of modules. Bundles simplify the handling of sets of related modules.