What is a noun?

A noun is a word that names something, such as a person, place, thing, or idea. In a sentence, nouns can play the role of subject, direct object, indirect object, subject complement, object complement, appositive, or adjective.

Different Types of Noun:
Proper Noun.
Common Noun.
Abstract Noun.
Concrete Noun.
Countable Noun.
Non-countable Noun.
Collective Noun.
Compound Noun.