Why must we use the first seven characters of a SHA hash to identify a commit?

Frequently Asked Questions Git FAQ
22

HI, what 7 characters means? I couldnt catch that.

23

You can exit by pressing q in the terminal. If you face this issue outside Codecademy’s virtual environment, press the esc key and then type :wq in the terminal. This is because Git uses the vi text editor to view the logs.