Hi, I'm Heather Kamins for About.com, and I'm here to talk to you about what is a noun.A noun is a part of speech that names a person, place or thing. Nouns can be single, like car or woman; or plural, like cars or women. Common nouns describe a general thing, like 'state.'Proper nouns describe a specific thing, like 'Vermont.' Proper nouns are generally capitalized. Nouns serve several different functions within sentences, most commonly as the subject. Every sentence has to have one, and that's the person, place or thing that does the action in the sentence. For example: the horse galloped away.A noun can also be an object in a sentence, and that's the thing that has the action done to it. So for example: the horse ate the apple. In that sentence, horse is the subject, apple is the object, and they're both nouns.Thanks for watching. To learn more, visit us on the web at About.com.