Interactively search through your command line history with a simple keyboard shortcut.
At a new shell prompt (bash or Terminal.app on Mac) press Ctrl-R
Start typing the search string to lookup in your bash history. As you type the top matching command in your history will appear.
Hit Return to accept the search and execute the matching command or Esc to cancel the search.
You can also hit the right-arrow to edit the command before running it.