A 3d scanner refers to a device, which analyzes objects, and collect data on it dimensions and shape. Laser scanning has many different types of uses, and 3D laser scanning is widely used in many different industries. Applications for civil surveying, reverse engineering and industrial architecture are some of is versatile uses. 3D laser scanning can produce higher resolution, and faster 3D digitizing than other more conventional techniques. Virtual reality techniques can be used to produce a virtual three dimensional space from the desired architecture, and then used in computer simulations. 3D laser scanning is also used to document rebar installations to allow inspection. Other applications can include the investigation of accidents. An accident can be 3D laser digitized, and a simulation of the accident produced allowing various possibilities to be explored. Different technologies are utilized in manufacturing 3D laser scanning devices, and each one has its limitations, advantages and disadvantages.