LGS (Legend Go Server) is an internet site for the GameOfGo - http://www.lgs.taiwango.net.
Do not be intimidated by the Chinese characters. You need to download a client to install on your PC, which will make use of an existing internet connection to link you up to real people players all over the world.
No you don't; there is a raw telnet interface. It is not terribly user-friendly however.
This is a friendly site where sometimes you can see 1000+ people online playing hundreds of games that you can observe, or participate in.