3D printing or additive manufacturing (AM) is any of various processes of making a three-dimensional object from a 3D model or other electronic data source primarily through additive processes in which successive layers of material are laid down under computer control.
A 3D printer is a type of industrial robot.
Early AM equipment and materials were developed in the 1980s. They were expensive and most required special handling. The names 3D printing and additive manufacturing did not yet have currency as umbrella terms for the field; each AM technology usually went by its own name. In 1984, Chuck Hull of 3D Systems Corp, invented a process known as stereolithography employing UV lasers to cure photopolymers. Hull also developed the STL file format widely accepted by 3D printing software, as well as the digital slicing and infill strategies common to many processes today. Also during the 1980s, the metal-sintering forms of AM were being developed (such as selective laser sintering and direct metal laser sintering), although they were not yet called 3D printing or AM at the time.