CTCP & DCC COMMANDS

CTCP stands for Client-To-Client-Protocol. The CTCP command performs certain client specific functions on the IRC network. It permits you to find out various kinds of information and perform some useful functions on IRC. Many clients allow you to use CTCP to customize various functions, such as setting up a file server on your system, or providing a means to grant op status to users when you are not there to do it yourself. CTCP commands can also be disabled by the user, so don't be surprised if you get no information back from a user when you initiate certain CTCP requests to them.

/ctcp [nick] ping - ping is used to determine the amount of time it takes for your signal (messages) to get to another nick and back in seconds. It measures the amount of lag time for the message. Excessive lag can make communication difficult.
/ctcp [nick] version - version is used to query a nicks' client for the type or name of the IRC program they are running
/ctcp [nick] finger - finger gives additional information about a nick. Sometimes it's not much different from the /whois [nick] information
/ctcp [nick] userinfo - the userinfo ctcp function usually gives about the same information as the finger reply
/ctcp [nick] clientinfo - clientinfo ctcp function will tell you what functions are active on the nicks' client. Can be useful if you want to know if things like DCC, ping, or finger are active on their system
/ctcp [nick] time - this checks the local date and time on a nick's computer. I guess it might be useful if you wanted to know what time it was in Australia, if you were talking to an Aussie