Exchanges are platforms for trading cryptoassets. Exchanges vary in several key respects: degree of centralization, method(s) of order matching, whether and how funds are custodied, businesses model, and degree of KYC/AML compliance. Centralized exchanges, such as Coinbase or Gemini, require users to deposit funds to a centrally-custodied account, with all order-matching completed off-chain by proprietary matching engines. Decentralized exchanges, such as Ethfinex, do not custody user funds and may use on-chain order-matching methods.