What does "message board" mean?

A board on which messages may be posted, especially one in a public space.

Message board

Common synonyms include: bbs, bulletin board, community forum, forum, notice board, online bulletin board.

noun

noun ·Rare ·Advanced level

Noun

1
A board on which messages may be posted, especially one in a public space.
2
A system by which users may send, read and reply to public messages; an electronic bulletin board or forum. Internet
"He busted in, blessed be the Lord / Who believe any mess they read up on a message board"
3
A communication board.
"Disabled lesbian spells out 'I love you' on message board."

"He busted in, blessed be the Lord / Who believe any mess they read up on a message board"