{{tag>protocol software internet chatrooms privacy}}
====== IRC ======
**IRC** is an protocol commonly used on the [[internet]] that facilitates a text-based [[online chat|chatroom]] environment. Typically, port ''6697'' is used with SSL, but historically IRC was a plaintext protocol using port ''6667''. 
===== Clients =====
  * [[Weechat]]
  * [[KVIrc]]
===== Design ===== 
==== Networks ====
IRC is designed to be a federated protocol, meaning that an IRC **network** can be accessible from various different official servers. This federated model can protect from network downtime, due to the lack of a single point of failure, as well as promote diplomacy among the network administration.  
==== Channels ====
Servers are grouped into channels. Channels start with a pound ''#'' symbol and can have various different modes set, represented by a string of flags. They can also have a topic, which is a string that is intended to represent the current topic of conversation, but nowadays is used more like a description for the channel.
==== Users ====
A user has four identifying attributes:
  * ''nickname'' How you will be seen in chat and user lists. Only ASCII. No spaces.
  * ''realname'' Optional field that supports spaces and unusual characters.
  * ''ident/username'' For SASL.
  * ''password'' (not shown to other clients)
Additionally, there is the user's IP and host, but those are not client defined. The IP is only seen by the server; but the host is shown to other clients. Usually the host is an rdns lookup of the client IP, a cloaked (hashed) version of the user's IP, or customized by the user after registering to preserve their [[anonymity]]. 
===== IRC client commands =====
Here are some commands broadly implemented by IRC clients.
  *''/join <channel>'' Subscribes you to a channel.  
  *''/part'' Leaves a channel and incurs a ''part'' message defined by your client.
  *''/whois <nick>'' Queries info about another person in the same channel.