Perl is a kind of scripting language. I'm not sure if thee is much of a use for it other than for using CGI files, but you can probably just go ahead and install it if you'd like.
It's a powerful tool for system admins. If you know how to use it, I would definitely recommend you install it. If you don't know it, it's obviously not going to be very useful.
Perl if an powerful scripting language that is weak typed, but that provides many tools and many addons. It also has a cgi ability, and that's why you probable heard of it. I recommand you to install it
Try Python (other scripting language), his syntax is easier than perl, it is very very powerful and it is object oriented.
Python can do anything which you want to do, admin scripts, GUI, sockets, databases, CGI scriptings, etc, anything.
Perl is a scripting language for designing web applications. I would recommend installing it: you might be able to use it later even if you aren't able to now.