bulletin board system vs bbs

bulletin board system and bbs both are nouns.

Word	Noun	Adjective	Verb	Adverb
bulletin board system	Yes	No	No	No
bbs	Yes	No	No	No

As nouns, bulletin board system and bbs are synonyms defined as:

bulletin board system and bbs: a computer that is running software that allows users to leave messages and access information of general interest

Other synonyms of bulletin board system include bulletin board, electronic bulletin board.

bulletin board system (noun)	bbs (noun)
a computer that is running software that allows users to leave messages and access information of general interest	a computer that is running software that allows users to leave messages and access information of general interest