promote vs contribute

promote and contribute both are verbs.

Word	Noun	Adjective	Verb	Adverb
promote	No	No	Yes	No
contribute	No	No	Yes	No

As verbs, contribute is a hyponym of promote; that is, contribute is a word with a more specific, narrower meaning than promote:

Other hyponyms of promote include connive at, wink at, cultivate, foster, further, spur, help, carry, feed, conduce, lead.

promote (verb)	contribute (verb)
make publicity for; try to sell (a product)	contribute to some cause
change a pawn for a better piece by advancing it to the eighth row, or change a checker piece for a more valuable piece by moving it to the row closest to your opponent	bestow a quality on
be changed for a superior chess or checker piece	provide
give a promotion to or assign to a higher position	be conducive to
contribute to the progress or growth of