The present technology provides a method of operating a host communicating with a memory system including a journal area and a data area. The method of operating the host includes determining to update old data stored in the memory system, transferring, to the memory system, a write command for writing journal data and meta journal data for updating the old data to the journal area, and transferring, to the memory system, a write command for writing new data corresponding to the journal data to the data area in response to a write completion of the meta journal data and the journal data received from the memory system. Each of the meta journal data and the journal data includes a descriptor identifier (ID) indicating the same write transaction.