A channel operator (commonly abbreviated as op) is a user that moderates a channel on a given network. They are responsible for maintaining the modes and topic of the channel, the banlist, and moderating any unwanted activity. Channel operators should not be confused with IRC operators, who enforce network, rather than channel, rules.
In many IRC networks, operators have different types of access in a channel. These ranks often depend upon the IRCd software used, although a few specific access levels remain fairly constant throughout variations:
In most cases, the person that first joins a channel automatically gets operator status, and is later referred to as the channel founder, which usually gives them further privileges on networks with ChanServ. Channel operators can also voice (+v) and op (+o) other users in the channel. On networks with no channel services, abuse of netsplits is common to gain operator status in certain channel. To grant someone with full operator privileges use the command /mode <#channel> +o <nickname>, use the alias /op <nickname> on the Mibbit client, or the user at AOP or user access level 5 via ChanServ.
Some servers feature halfops (+h). These users are privileged in a certain channel, though not as powerful as ops. Halfops may kick other users out of the channel and set most channel modes. In addition, they can also set voice (+v) to all users. They are not allowed to make other users ops or halfops. This is supported on IRCds such as UnrealIRCd and UltimateIRCd. Other IRCds, such as Bahamut and ircu, do not have halfops. Mibbit IRC network runs UnrealIRCd and supports halfops (+h). In some IRC clients (such as mIRC and Irssi or Mibbit through Preferences), ops and halfops are represented by an "@" or a "%", respectively, prepended to the user's name in the channel's userlist or chat window. To grant someone with half operator privileges use the command /mode <#channel> +h <nickname> or add the user at HOP or user access level 4 via ChanServ.
The network runs UnrealIRCd which introduces two extra channel privileges.
Channel owner (+q) has the highest privilege and thus only other channel owners (+q) can set modes, or kick a user with this privilege. To grant someone with owner privileges use the command /mode <#channel> +q <nickname>.
Channel administrator (+a) has the second highest privilege thus only other channel owners (+q) can set modes, or kick a user with this privilege. To grant someone with administrator privileges use the command /mode <#channel> +a <nickname> or add the user at SOP or user access level 10 via ChanServ.
When a channel is initially created, that user is granted operator status. That user may carry out usual operator status functions, including giving other users operator status, setting a channel topic, and changing the channel modes. If all the users with operator or half operator status leave a channel, but other users remain, it is impossible to obtain operator status until everybody leaves the channel. This problem can be mitigated by registering the channel, which allows for an auto op list.