Noun shows the name of a person, place, animal, object, and ocassion. They are classified into two groups:
Proper noun Common noun
Examples: Name: Mrs. Rocelyn woman/ lady
Place: Bagio city
Animal: Brownie dog
Object: Faber Castel pencil
Ocassion: Flores De Mayo special event
Pronoun replace nouns. We need replacement from nouns because it is hard to and dangerous to specifically anounce your/ his/ her name. Examples of these are he, she, and them.
Example: (Without any replacement/ pronoun and opposite and the cause of no pronouns)
The person was now in danger who you introduced which is not face to face in front of that stranger because you specifically announced the name and there were no pronouns. Now the stranger Plans to steal her account and post some unnapropriate images you see and you were too shocked to see those images and your friend was also too dissapointed. Now you were thinking like "Oh no, im in big trouble now. I wished that i have'nt told the name of my friend...." Now your friend finds out you told the name and the account she gets mad at you and blames for you because you were not too smart to know the cause of telling it to the stranger.
Example: (With a replacement of nouns into pronouns and their good cause)
She/ he and everyone can be safe from from dangers because of the pronouns. You are safe from strangers from getting into your address and email account. Which is actually a very good cause of the pronouns
Hope these helps. Actually it took me a long time to type these out. ^_^