.vimrc is the configuration file for vim. Upon execution vim will read the contents of this file setting up a customized environment. You have to save this file in your home directory. It is important to notice that the commands should not include the initial colon (:).

Here are some useful commands:

syntax on          " syntax highlighing
set number         " show line numbers
set ruler          " show the cursor position all the time
set ignorecase     " ignore case when searching
set hlsearch       " highlight searches
set tabstop=4      " number of spaces of tab character
set shiftwidth=4   " number of spaces to (auto)indent
set autoindent     " always set auto indenting on
set smartindent    " smart indent
set cindent        " cindent

If you are using vi instead of vim, then save your configuration to ~/.exrc

Be careful not to leave a final end of line or vi will complain it does not understand the command.

set sm
set number
set ignorecase
set tabstop=4
set shiftwidth=4
set autoindent
set showmatch
set ruler