identity vs unity

identity and unity both are nouns.

Word	Noun	Adjective	Verb	Adverb
identity	Yes	No	No	No
unity	Yes	No	No	No

As nouns, unity is a hyponym of identity; that is, unity is a word with a more specific, narrower meaning than identity:

Other hyponyms of identity include oneness, selfsameness.

identity (noun)	unity (noun)
the distinct personality of an individual regarded as a persisting entity	the quality of being united into one
exact sameness	the smallest whole number or a numeral representing this number
the individual characteristics by which a thing or person is recognized or known	an undivided or unbroken completeness or totality with nothing wanting
an operator that leaves unchanged the element on which it operates