NFTs are used to represent ownership of a unique item. They let us tokenize things like art, pictures, in game items, domain name, ticket to an event, essay or intellectual property, collectible, original music, real estate or literally anything that is an original. No one can modify the record of ownership or copy/paste the new NFT into existence. The value comes from it’s scarcity. The purpose of having them on the blockchain is to easily transfer ownership, record each transfer as a permanent record and provide a way for the original creator to benefit from the increase in price value.