A sending/receiving method for data, such as musical data, in which plural data stored in a first storage unit are retrieved based on the request information sent from a host side device. The retrieved data is sent to a terminal side device. The sent data is checked to see as to whether or not the sent data is data newly stored in the first storage unit. If the results of check indicate that the sent data is data newly stored in the first storage unit, the sent data is stored in a second storage unit of the terminal side device.