VIM (VIsual editor iMproved) is an updated and improved version of the vi editor. Vi was the first real screen-based editor for UNIX, and is still very popular. VIM improves on vi by adding new features: multiple windows, multi-level undo, block highlighting and more. The vim-common package contains files which every VIM binary will need in order to run.
If you are installing vim-enhanced or vim-X11, you'll also need to install the vim-common package.