black and white vs written language

black and white and written language both are nouns.

Word	Noun	Adjective	Verb	Adverb
black and white	Yes	Yes	No	No
written language	Yes	No	No	No

As nouns, black and white and written language are synonyms defined as:

black and white and written language: communication by means of written symbols (either printed or handwritten)

Other synonyms of black and white include written communication.

black and white (noun)	written language (noun)
a black-and-white photograph or slide	communication by means of written symbols (either printed or handwritten)
communication by means of written symbols (either printed or handwritten)

black and white (adjective)	written language (adjective)
not having or not capable of producing colors