Freenode

freenode (known before as Open Projects Network), is an IRC network. It is used to discuss peer-directed projects. The freenode servers can all be used from the domain name chat.freenode.net. This automatically switches the user to one of the actual servers in use. As of 2010, it was the largest free and open source software-focused IRC network. It had more than 70,000 users and 40,000 channels.
History.
freenode began as a 4-person Linux support channel called #LinPeople on EFnet. EFnet was another IRC network. By 1995 it had moved from being just a channel to its own network, irc.linpeople.org. In early 1998 it changed to Open Projects Net (OPN0). It had about 200 users and under 20 channels.
On June 24, 2006, a user with the nickname "ratbert" managed to get the staff rights of Rob Levin (lilo) and took control of the network. It is believed that around 25 user passwords were stolen because of this. This user K-lined many freenode staff members. Most freenode servers went down for several hours because of this.
Channels.
The network focuses on supporting peer-directed and open source projects. Channels which are not related to these things are off-topic on freenode. They are encouraged to find a home somewhere else. To support this, channels are divided. On-topic channels begin with a single #. Groups who want to use one of these channels must officially register with freenode. Off-topic channels begin with ##. These can be used without a group registration.