The ATMC102U is a mini color USB camera, used in the medical care, microscope, video conferencing, video phones,video email, PC multimedia, toys, industry pipe & well inspection, CCTV security surveillances, etc. This mini USB camera has 2 units: a camera head and a USB video converter. The former has analog video/audio output signals,the latter converts the analog signals into digital ones with a USB protocol which allows interfacing to a computer conveniently. There are 4 wires between the 2 units.