The GIF Ms. Jin sold, created by her childhood friend, an artist named Annie Zhao, is an example of something called a nonfungible token. NFTs are essentially digital collectible items (GIFs, images, memes, games, code, videos, artwork, music, games, even text) that people can buy, sell and trade. Almost any piece of digital content can be made into an NFT and have its public documentation of ownership recorded on the blockchain. Some of the ideas behind NFTs — documentation of ownership and chain of custody, scarcity, trading, valuations and speculation — are as old as markets. The innovation is the decentralization, which in turn means you can take NFTs anywhere. No one platform or middleman controls them.