Whois

Whois is an IRC command used for getting information about someone. To perform it use:

/whois nick

or

/whois nick nick

The latter command will request a whois from the target's local server, so will show their idle time as well as other information.

A Complete whois on me gives:

mist|zZz is [email protected] * misty
mist|zZz on #pawiki #elysium #fury #planetarion #cservice 
mist|zZz using London.UK.Eu.Netgamers.org Mmmmmmmm pie,pie,pie,PIE!!!
mist|zZz is logged in as mist
mist|zZz has been idle 6mins 18secs, signed on Fri Dec 31 12:57:49
mist|zZz End of /WHOIS list.

Broken down, this gives:

mist|zZz is [email protected] * misty

My hostmask, which is mist|[email protected] - note that i'm using the user mode +x to hide my real ip address. It then gives my name.

mist|zZz on #pawiki #elysium #fury #planetarion #cservice

The IRC channels i'm on.

mist|zZz using London.UK.Eu.Netgamers.org Mmmmmmmm pie,pie,pie,PIE!!!

The Server i'm connected to. If you whois someone else you won't be told their server, but will get a message like:

mist|zZz using *.netgamers.org The NetGamers IRC Network

instead.

mist|zZz is logged in as mist

Shows my registered nick (nicks ending in |zZz can't be registered). If someone is not logged on this line is omitted.

mist|zZz has been idle 6mins 18secs, signed on Fri Dec 31 12:57:49

Gives my idle time.