[Apache::Registry] is the part of [mod_perl] that will [compile], [cache] and [execute] your [perl] [CGI] [script|scripts] within a pseudo-[CGI] environment. What makes [Apache::Registry] so great is that it allows you to use all of your old [perl] [CGI] [script|scripts] without any significant modification. [CGI] [script|scripts] run under [Apache::Registry] are much faster than before, sometimes by a couple of [order of magnitude|orders of magnitude].

Often when someone says that they use [mod_perl] on their [web server], they really mean they use [Apache::Registry] to speed up their [perl] [CGI|CGI's] rather then actually using the [full power] of [mod_perl] to do [authenticate|authentication] or sophisticated [content handler|content handling] or something.

[Apache::Registry] [kick ass|kicks ass] for [deploy|deployment], but it kind of [suck|sucks] for [develop|development] because it doesn't check the [use|use'd] and [require|require'd] [perl module|perl modules] to see if they have changed (unless you use [Apache::StatINC], but then you need to [develop] your [perl module|perl modules] in a [directory] in [@INC].)