A noun is one of the eight parts of speech that are fundamental to learning English. Imagine if there were no nouns. How would you identify your friends or pets? How would you convey an idea to someone? How would you show your feelings to your loved ones? By using nouns you can name people, objects, animals, places, events, quantities and countries and you can also convey feelings and ideas.
In English we use the eight parts of speech in a manner that is understandable to everyone and one of the important elements of this is the interrelationship between the eight parts of speech. By themselves the eight parts of speech have different characteristics and each has a role to play. One of the fundamental structures of English is the sentence.