append vs add

append and add both are verbs.

Word	Noun	Adjective	Verb	Adverb
append	No	No	Yes	No
add	No	No	Yes	No

As verbs, append and add are synonyms defined as:

Other synonyms of append include supply.

append (verb)	add (verb)
state or say further	make an addition (to); join or combine or unite with others; increase the quality, quantity, size or scope of
fix to; attach	make an addition by combining numbers
add to the very end	determine the sum of
	state or say further
	bestow a quality on
	constitute an addition