The electronics sector produces electronic equipment for industries and consumer electronics products, such as mobile devices, televisions, and circuit boards. Industries within electronics include telecommunications, equipment, electronic components, industrial electronics, and consumer electronics. Electronics companies may produce electrical equipment, manufacture electrical components, and sell items at retail to make their products available for consumers.
The electronics industry emerged in the 20th century and is today one of the largest global industries. Contemporary society uses a vast array of electronic devices built in automated or semi-automated factories operated by the industry. Products are primarily assembled from metal-oxide-semiconductor (MOS) transistors and integrated circuits, the latter principally by photolithography and often on printed circuit boards.