For many years now, Ethereum has been at the forefront of the smart contract and decentralized application industry. The blockchain hosted the first widely-used collectible game, the now-infamous CryptoKitties; much of 2017’s countless initial coin offerings; and one of the largest crypto-centric prediction markets, Augur.
Some of these applications of Ethereum have been enabled by tokens, namely those of the ERC-20 and ERC-721 variant. Binance Coin, for instance, was a widely-used ERC-20 token when it launched in mid-2017. And the adorable creatures you purchase, breed, and sell in CryptoKitties are ERC-721 tokens.