A 3D scanner is a device that analyses a real-world object or environment to collect data on its shape and possibly its appearance. From that collected data it can then be used to construct a digital three dimensional object.
Many different technologies can be used to build these 3D-scanning devices; each technology comes with its own limitations, advantages and costs. The purpose of a 3D scanner is usually to create a point cloud of geometric samples on the surface of the subject. These points can then be used to extrapolate the shape of the subject.. If colour information is collected at each point, then the colours on the surface of the subject can also be determined.
figure 1.1 A 3D model scanned from a human model