7) Ctl-Z — Background a unix process
Ctl-Z (or Control-Z on your keyboard) is “background” which means “send the process to the background.” It frees up your shell prompt for more commands but keeps the process running. When you hit Ctl-Z, Rails says this slightly confusing message:
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What’s slightly confusing is that the app isn’t actually stopped at all, it is now just running in the background. (See #9)