Speaking of MAC computers, here's how you can make a quick screenshot of a specific section on your desktop/laptop: Shift + ...

Get more screen space, better input devices, and a more comfortable overall setup for when you're sitting at your desk using the computer.

Finger was a common service provided by computer services at the time. It was like a LinkedIn profile page for the 1970s. Modern versions may also show your public PGP key and other data.