program library vs collection

program library and collection both are nouns.

Word	Noun	Adjective	Verb	Adverb
program library	Yes	No	No	No
collection	Yes	No	No	No

As nouns, collection is a hypernym of program library; that is, collection is a word with a broader meaning than program library:

program library: (computing) a collection of standard programs and subroutines that are stored and available for immediate use
collection: several things grouped together or considered as a whole

Other hypernyms of program library include accumulation, aggregation, assemblage.

program library (noun)	collection (noun)
(computing) a collection of standard programs and subroutines that are stored and available for immediate use	the act of gathering something together
	a publication containing a variety of works
	request for a sum of money
	several things grouped together or considered as a whole