VI Improved is a common derivate of the default editor on Unix-like systems. Usually, $EDITOR is also set to vi or vim.
vi is everywhere, but vim is not.
A quick configuration which you can use to get basic stuff like syntax coloring, ready made to past into your .vimrc:
set nocompatible syntax on filetype plugin indent on set hlsearch set history=50 set showmode set showcmd cabbrev Wq wq cabbrev W w colorscheme desert
The desert colorscheme will let you read comments (which are normally dark-blue) also on wrong-configured terminals and looks pretty good elsewhere too.