A coin is a cryptocurrency that is the native asset on its own blockchain. These cryptocurrencies are required to pay for transaction fees and basic operations on the blockchain. BTC (Bitcoin) and ETH (Ethereum) are examples of coins. Tokens, on the other hand, are crypto assets that have been issued on top of other blockchain networks. The most popular platform for issuing tokens is Ethereum, and examples of Ethereum-based tokens are MKR, UNI and YFI. Even though you can freely transact with these tokens, you cannot use them to pay Ethereum transaction fees.