This is a class file to demonstrate how Twitter bootstrap works and how to use the LESS compiler. The preferred method for me is to use the Node Package Manager and install Less as a global install, then use Sublime Text Editor to install packages.
The two packages are syntax highlighting for less and the automatic compiler from less to css. The other method is to use LiveReload,Simpless, or WinLess or some other GUI based system and have that watch a file and compile it for you.
If you do not have these files, the main less file is still there, although this client-side workflow is not recommended for performance reasons.