A host for controlling a non-volatile memory card, a system including the same, and methods of operating the host and the system are provided. The method of operating the host connected with the non-volatile memory card through a clock bus, a command bus, and one or more data buses includes transmitting a first command to the non-volatile memory card through the command bus, transmitting first data corresponding to the first command to the non-volatile memory card through the one or more data buses or receiving the first data from the non-volatile memory card through the data buses, and transmitting a second command to the non-volatile memory card at least once through the command bus during or before transfer of the first data.