writer vs Roberts

writer and Roberts both are nouns.

Word	Noun	Adjective	Verb	Adverb
writer	Yes	No	No	No
Roberts	Yes	No	No	No

writer (noun)	Roberts (noun)
writes (books or stories or articles or the like) professionally (for pay)	a Welsh pirate credited with having taken more than 400 ships (1682-1722)
a person who is able to write and has written something	United States writer remembered for his historical novels about colonial America (1885-1957)
	United States evangelist (born 1918)
	United States biochemist (born in England) honored for his discovery that some genes contain introns (born in 1943)