1. Clone a Git repository.
    $ git clone
  2. Add a file.
    $ git add readme.txt
  3. Commit a file.
    $ git commit -m "added readme file" readme.txt
  4. Push a file up to the Git master.
    $ git push


  1. SSH into an EC2 instance.
    $ ssh -i cd29.pem


  1. List files in a directory.
    $ ls -las
  2. Change permissions on a private key file.
    $ chmod 400 cd29.pem
  3. Open a file in vim.
    $ sudo vim filename.txt
  4. Close a file in vim without saving.
    $ <ESC>:q!
  5. Save and close a file in vim.
    $ <ESC>:wq!