A digital camera system comprising; a digital camera and a peripheral; the digital camera including: an image data memory for storing image data; an information input section adapted for inputting, from the peripheral, information usable for processing image data so as to be suitable for being output at the peripheral; an information memory adapted for storing a plurality of application programs; a discriminating means adapted for discriminating the type of the peripheral and an application program name corresponding to the peripheral when the digital camera is connected to the peripheral; an information selecting means adapted to select an application program among a plurality of the application programs stored in the information memory on the basis of the type of the peripheral discriminated by the discriminating means; a comparing means for comparing the application program name discriminated by the discriminating means and the application program selected by the information selecting means, for deciding whether the application program stored in the peripheral coincides with the selected application program or not; display means adapted to show a display for the user to select to read an application program stored in the peripheral, or means adapted to read automatically the application program stored in the peripheral, when the application program stored in the peripheral does not coincide with the selected application program; a processing means for processing the image data on the basis of the selected application program; and an image data output section adapted to output the processed image data to the peripheral; and the peripheral including: an application program memory adapted to store at least one application program; an information memory adapted to store an information regarding to said at least one application program stored in the application program memory; an information output section adapted to output the information to the digital camera; an image data input section adapted to input processed image data from the digital camera; a memory adapted to store the processed image data; and an executing means adapted to execute the application program by inputting the processing image data stored in the memory into the application program. an image data memory for storing image data; an information input section adapted for inputting, from the peripheral, information usable for processing image data so as to be suitable for being output at the peripheral; an information memory adapted for storing a plurality of application programs; a discriminating means adapted for discriminating the type of the peripheral and an application program name corresponding to the peripheral when the digital camera is connected to the peripheral; an information selecting means adapted to select an application program among a plurality of the application programs stored in the information memory on the basis of the type of the peripheral discriminated by the discriminating means; a comparing means for comparing the application program name discriminated by the discriminating means and the application program selected by the information selecting means, for deciding whether the application program stored in the peripheral coincides with the selected application program or not; display means adapted to show a display for the user to select to read an application program stored in the peripheral, or means adapted to read automatically the application program stored in the peripheral, when the application program stored in the peripheral does not coincide with the selected application program; a processing means for processing the image data on the basis of the selected application program; and an image data output section adapted to output the processed image data to the peripheral; and the peripheral including: an application program memory adapted to store at least one application program; an information memory adapted to store an information regarding to said at least one application program stored in the application program memory; an information output section adapted to output the information to the digital camera; an image data input section adapted to input processed image data from the digital camera; a memory adapted to store the processed image data; and an executing means adapted to execute the application program by inputting the processing image data stored in the memory into the application program. an application program memory adapted to store at least one application program; an information memory adapted to store an information regarding to said at least one application program stored in the application program memory; an information output section adapted to output the information to the digital camera; an image data input section adapted to input processed image data from the digital camera; a memory adapted to store the processed image data; and an executing means adapted to execute the application program by inputting the processing image data stored in the memory into the application program.