APT (Automatically Programmed Tool) is a high-level computer programming language most commonly used to generate instructions for numerically controlled machine tools. Douglas T. Ross is considered by many to be the father of APT: as head of the newly created Computer Applications Group of the Servomechanisms Laboratory at MIT in 1956, he led its technical effort. APT is a language and system that alleviates the tedious mathematics of writing toolpaths for numerically controlled equipment. This early language was used widely through the 1970s and is still a standard internationally. Derivatives of APT were later developed.