Short Story: el-get allows you to install and manage +elisp+ code for
Emacs. It supports lots of differents types of sources and is able to
'install' them, 'update' them and 'remove' them, but more importantly it
will 'init' them for you.
That means it will +require+ the 'features' you need, +load+ the
necessary files, set the 'Info' paths so that +C-h i+ shows the new
:description "A mode for interfacing with Growl, Snarl, and the like."