human being vs man

human being and man both are nouns.

Word	Noun	Adjective	Verb	Adverb
human being	Yes	No	No	No
man	Yes	No	Yes	No

As nouns, human being and man are synonyms defined as:

human being and man: any living or extinct member of the family Hominidae characterized by superior intelligence, articulate speech, and erect carriage

Other synonyms of human being include homo, human.

As nouns, man is a hyponym of human being; that is, man is a word with a more specific, narrower meaning than human being:

human being: any living or extinct member of the family Hominidae characterized by superior intelligence, articulate speech, and erect carriage
man: all of the living human inhabitants of the earth

human being (noun)	man (noun)
any living or extinct member of the family Hominidae characterized by superior intelligence, articulate speech, and erect carriage	all of the living human inhabitants of the earth
	any living or extinct member of the family Hominidae characterized by superior intelligence, articulate speech, and erect carriage
	game equipment consisting of an object used in playing certain board games
	an adult person who is male (as opposed to a woman)
	someone who serves in the armed forces; a member of a military force
	the generic use of the word to refer to any human being
	a manservant who acts as a personal attendant to his employer
	an adult male person who has a manly character (virile and courageous competent)
	a male person who plays a significant role (husband or lover or boyfriend) in the life of a particular woman
	a male subordinate

human being (verb)	man (verb)
	provide with workers
	take charge of a certain job; occupy a certain work place