K-line is an IRC term. It stands for a line in the configuration file of the IRC server, that prevents a client with a specific hostmask to connect. Such a user is then called 'k-lined'.
Reasons for a client being k-lined include:
- Geography: If a IRC network has servers in different countries and continents, it will try to reduce the distance between server and client. Thus, servers on one continent may k-line all clients from the others and vice versa.
- Infected client: A client infected by a virus, worm or trojan that spreads via IRC may be k-lined, so it doesn't reduce the efficiency of the server and to decrease the rate at which the malicious program is spreading.
- Misbehaviour: If a user repeatingly disobeys the rules of the IRC network, and doesn't change his behaviour through kicks and bans, then he/she might get k-lined to protect the other users of the server.
An akill is a network-wide k-line that is done through Operserv
A q-line is a ban on a nickname on a server