USB and IEEE1394 are one kind of general external instrumentation connection, USB are an external bus standard, uses in the standard computer and external instrumentation's connection and the communication. The USB connection supports the pluf and play and hotly pull. They widely apply now in the computer, the camera, the digital camera and so in each kind of information equipment, the IEEE-1394 connection is suitable the digital image formation domain massively, supports product including digital camera/camera/facsimile/printer and so on.