Lists channel name, user count, and topic information for the network/server you are attached to.  If you omit the optional channel argument, all channels will be listed.  On large networks, the server may disconnect you for asking for a complete list.
列出您所连接的网络/服务器的频道名称、用户计数和主题信息。如果省略可选的频道参数，将列出所有频道。在大型网络上，服务器可能会因您要求完整列表而断开连接。