Prevents a hostmask from entering the channel. Example: /mode #cars +b ricky!IrCQNet@icq.com = bans ricky from entering #cars. This is the famous (or infamous) ban command. Not a channel setting per se, but is a flag that is assigned to a hostmask for that channel.

Note that the definition does NOT say anything about kicking...a ban is not a kick, they are two separate actions. Alot of misunderstanding is associated with bans due to clients/scripts combining those two actions together. A straight ban ONLY prevents channel entry. If the hostmask is already in the channel, the ban does nothing to them.

Note that the definition does not say anything about preventing a USER from entering. Servers have no way of knowing who is behind a hostmask; servers don't have psychic powers. If a user has the ability to change nicks/usernames/hosts at will, then there will be no reasonable way to keep them out of a channel except by drastic measures such as key (+k), invite only (+i), Restricted channel (done with Chanserv), etc.

The ban victim can be entered into the /mode command in several ways. If only a nick or host is entered, the server will attempt to fill in the remaining hostmask with wildcards.

All the bans for a channel are listed in that channel's ban list. To see the list in #cars, use /mode #cars b .If you use a client like mIRC, you can also get the banlist by doubleclicking on any open whitespace in the channel (this brings up Channel Central).

Bans can be set/removed by anyone who is presently opped or halfopped.

Ban exception. Example: /mode #cars +e ricky!IrCQNet@te48.aol.com. Not a channel setting per se, but is a flag that is assigned to a hostmask for that channel.

This will exempt a hostmask from being banned. Say for example that there was a broad ban in #cars such as *!*@*.aol.com. This ban would keep out all aol users. Giving ricky an exemption would let him (and only him) thru the ban.
Exemptions can be set/removed by anyone who is presently opped or halfopped.

Gives halfop status to a nick in the channel. Example: /mode #cars +k ricky = makes ricky a halfop in #cars. Not a channel setting per se, but is a flag that is assigned to a nick for that channel.

Nicks with a halfop flag are designated in the nicklist with a % in front of their nick and also have a % in their /whois next to the channel. Halfops can: give/take voice, kick users, set bans. Halfops cannot: give/take op, give/take halfop, invite, kick ops, kick halfops, assign other channel modes. Can also be assigned by Chanserv thru the access list and by the /cs halfop command.

Gives operator status to a nick in the channel. Example: /mode #cars +o ricky = makes ricky an op in #cars. Not a channel setting per se, but is a flag that is assigned to a nick for that channel.

Nicks with an op flag are designated in the nicklist with a @ in front of their nick and also have a @ in their /whois next to the channel. Ops can (generally speaking) kick/ban/exempt anyone, can assign voice and halfops, and can set channel modes.

Private channel. Example: /mode #cars +p. A private channel will not show up with the /list command. Nicks in a private channel will not show up with the /names #channel nor /who #channel commands.

I don't know of any difference between a private channel and a secret (+s) channel.

Channel set to "Auditorium". Example: /mode #cars +u. Normally, when a user first joins a channel, their client does a /names command for that channel and creates its nicklist from the resulting output. After that, the client uses joins and parts to keep the nicklist updated. A channel set to +u however, will filter that output such that only ops/halfops/+a/+q will be seen. In addition, all joins and parts are blocked from being seen by users/voices.

The effects of +u on a channel can be disconcerting to users who are not used to that mode. The following is short summary:

For ops/halfops/+a/+q who are already in the +u channel, there is no affect. All nicks can be seen in the nicklist and all joins/parts are sent to them by the server. However, when an op or halfop first joins, they do not have their op status and so they begin as a user. After receiving op/halfop, they must use /names #channel to refresh their nicklist. During the time that they were not op/halfop, they will not have seen any joins/parts.

For normal users and voices: When first entering a channel, they will only see ops/halfops/+a/+q. They will not see any normal users nor voices. They will not see anyone join or part in the channel. Even if an op leaves, the user will not see the channel part message and the op's nick will remain in the nicklist. Quits are not affected by +u. They will still be seen in the channel. Channel chat is not affected by +u. All chat, even from normal users and voices, can still be seen. However, the chat will seem to come from invisible users (which is a fairly accurate description). The nick of the chatter will still preceed the chat lines, but you will not see the nick in the nicklist. In addition to affecting /names, the /who command can be affected as well.

Gives voice to a nick in the channel. Example: /mode #cars +v ricky = gives ricky voice in channel #cars. Not a channel setting per se, but is a flag that is assigned to a nick for that channel.

The original purpose of the voice funtion was to help control user channel chat in special situations. In a moderated channel (one with +m set), only ops, halfops and voices can send text to the channel and so a channel can be made to act as a meeting hall, with only one speaker talking at a time. However, +m and voice can also be used to limit floods during flood attacks. Voice is also sometimes used for showing favorable recognition.

Nicks with voice are designated in the nicklist with a + in front of their nick and also have a + in their /whois next to the channel. Can also be assigned by Chanserv thru the access list and by the /cs voice command.