data processor vs computer

data processor and computer both are nouns.

Word	Noun	Adjective	Verb	Adverb
data processor	Yes	No	No	No
computer	Yes	No	No	No

As nouns, data processor and computer are synonyms defined as:

data processor and computer: a machine for performing calculations automatically

data processor (noun)	computer (noun)
a machine for performing calculations automatically	a machine for performing calculations automatically
	an expert at calculation (or at operating calculating machines)