behavior vs manners

behavior and manners both are nouns.

Word	Noun	Adjective	Verb	Adverb
behavior	Yes	No	No	No
manners	Yes	No	No	No

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

behavior: (behavioral attributes) the way a person behaves toward other people
manners: social deportment

behavior (noun)	manners (noun)
manner of acting or controlling yourself	social deportment
(psychology) the aggregate of the responses or reactions or movements made by an organism in any situation
(behavioral attributes) the way a person behaves toward other people
the action or reaction of something (as a machine or substance) under specified circumstances