finger

Look up local user

$ finger [username]

$ finger [username]@[host]

$ finger

$ finger -l [username]

$ finger -s [username]

finger [options] [user...] [user@host...]

finger displays information about system users including name, terminal, login time, and contact information. It reads from system databases and user home directories.
Users can customize their finger output with .plan and .project files in their home directory. Remote finger queries contact the finger daemon on port 79.
finger was once common for finding contact information on multi-user systems and across the early internet.

USER

Username to look up.

Remote user lookup.

Long format output.

Short format output.

Match exact username only.

Omit .plan and .project files.

Display help information.

Privacy concerns led to disabling on most systems. Remote finger is often blocked. Information disclosure can be a security risk.

finger originated at Stanford in 1971 and became a standard Unix utility. Once ubiquitous for user lookup, it's now largely deprecated due to privacy and security concerns.

who(1), w(1), pinky(1)