Chinese campus BBSes dominated student internet life in the late 90s and 2000s. 水木清华 (Tsinghua), 北大未名 (Peking U), and 复旦日月光华 were the big three; many shaped internet subculture and slang that now feels mainstream.
usage
Pronounced letter-by-letter in English. Sometimes spelled 论坛 (lùntán) in Chinese generically, but 'BBS' retains a specific old-school connotation.