This section has an explanation about using yToken tokens.
Each market has related token and it's ID. It allows users to operate their liquidity as one of yTokens that bound to lending market.
Entrypoints
transfer
Allows transfer batch (list) of token transfers. Each transfer in the batch is specified between one source (from_) address and a list of destinations. Each destination specifies token_id, the amount to be transferred from the source and address of the destination (to_).
FA2 interface specifies an entrypoint to update operators. Operators are permitted per specific token owner and token ID (token_id). Once permitted, an operator can transfer tokens of that type belonging to the owner. To update own tokens operators user should use update_oprators call.
Gets the balance of multiple account/token pairs. Accepts a list of balance_of_requests (token_id and owner) and a callback contract callback which accepts a list of balance_of_response (balance_of_request and requested balance) records.