Keller vs author

Keller and author both are nouns.

Word	Noun	Adjective	Verb	Adverb
Keller	Yes	No	No	No
author	Yes	No	Yes	No

Keller (noun)	author (noun)
United States lecturer and writer who was blind and deaf from the age of 19 months; Anne Sullivan taught her to read and write and speak; Helen Keller graduated from college and went on to champion the cause of blind and deaf people (1880-1968)	writes (books or stories or articles or the like) professionally (for pay)
	someone who originates or causes or initiates something

Keller (verb)	author (verb)
	be the author of