Assume you have a tarball project.tar.gz with your initial work.
You can place it under Git revision control as follows.
$ tar xzf project.tar.gz
$ cd project
$ git init
Git will reply
Initialized empty Git repository in .git/
You've now initialized the working directory—you may notice a new
directory created, named ".git".
Next, tell Git to take a snapshot of the contents of all files
under the current directory (note the .), with git add:
$ git add .
This snapshot is now stored in a temporary staging area which Git
calls the "index". You can permanently store the contents of the
index in the repository with git commit:
$ git commit
This will prompt you for a commit message. You've now stored the
first version of your project in Git.
