You Don’t Need to Be In Who’s Who to Know What’s What
If you have an account on a UNIX machine, UNIX knows a great deal about you. (Not that we’re paranoid.) It knows your username, when you last logged on, which terminal you are using, and possibly additional facts, such as your real name and office extension, and it writes a short essay about what you are up to. (No, we’re not kidding. Read on.) Other people can see this information, including people who use the same computer as you, and (if your UNIX system is on a network) people who use other computers.