The major difference between nouns and verbs is how they function in language. Nouns identify people, places, things or qualities, while verbs describe an action or a state of being.
A noun is the basic building block of the subject of a sentence, and a verb serves that purpose in the predicate. Nouns can be modified by adjectives, but verbs cannot. Verbs are modified instead by adverbs. Verbs have tense, while nouns do not. Tense deals with time. The tense of a verb indicates when an action takes place. Some words, such as "rain" or "love," can be nouns or verbs, depending on how they are used in a sentence.