Editing CPAN (section)

==Structure==
Files on the CPAN are referred to as ''distributions''. A distribution may consist of one or more modules, documentation files, or programs packaged in a common archiving format, such as a [[gzip]]ped [[tar file format|tar]] archive or a [[ZIP file format|ZIP]] file. Distributions will often contain installation scripts (usually called ''Makefile.PL'' or ''Build.PL'') and test scripts which can be run to verify the contents of the distribution are functioning properly. New distributions are uploaded to the Perl Authors Upload Server, or PAUSE (see the section [[#Uploading distributions with PAUSE|Uploading distributions with PAUSE]]).

In 2003, distributions started to include metadata files, called ''META.[[YAML|yml]]'', indicating the distribution's name, version, dependencies, and other useful information; however, not all distributions contain metadata. When metadata is not present in a distribution, the PAUSE's software will try to analyze the code in the distribution to look for the same information; this is not necessarily very reliable. In 2010, version 2 of this specification was created<ref>{{cite web |title=CPAN::Meta::History |url=https://metacpan.org/pod/CPAN::Meta::History |access-date=20 December 2019}}</ref> to be used via a new file called ''META.[[json]]'', with the YAML format file often also included for [[backward compatibility]].

With thousands of distributions, CPAN needs to be structured to be useful. Authors often place their modules in the natural hierarchy of Perl module names (such as <code>Apache::DBI</code> or <code>Lingua::EN::Inflect</code>) according to purpose or domain, though this is not enforced.

CPAN module distributions usually have names in the form of ''CGI-Application-3.1'' (where the '''::''' used in the module's name has been replaced with a dash, and the version number has been appended to the name), but this is only a convention; many prominent distributions break the convention, especially those that contain multiple modules. Security restrictions prevent a distribution from ever being replaced with an identical filename, so virtually all distribution names do include a [[version number]].