later vs afterwards

later is an adjective but afterwards is not an adjective.

Word	Noun	Adjective	Verb	Adverb
later	No	Yes	No	Yes
afterwards	No	No	No	Yes

As adverbs, later and afterwards are synonyms defined as:

later and afterwards: happening at a time subsequent to a reference time

Other synonyms of later include after, afterward, later on, subsequently.

later (adjective)	afterwards (adjective)
at or toward an end or late period or stage of development
coming at a subsequent time or stage

later (adverb)	afterwards (adverb)
happening at a time subsequent to a reference time	happening at a time subsequent to a reference time
at some eventual time in the future
comparative of the adverb `late'