Fugitive Vim is a plugin by Tim Pope that provides access to git commands that you can execute without leaving vim.
Some common commands include:
:Gedit - edit a file in the index and write it to stage the the changes
:Gstatus - equivalent of git status
:Gblame - brings up vertical split of output from git blame
:Gmove - for git mv
:Gremove - for git rm
:Git - run any command
It also adds items to the statusline like indicating the current branch.
Please see their GitHub for more details and installation instructions.