The electronics industry is the economic sector that produces electronic devices. It emerged in the 20th century and is today one of the largest global industries. Contemporary society uses a vast array of electronic devices that are built in factories operated by the industry, which are almost always partially automated.
Electronic products are primarily assembled from metal–oxide–semiconductor (MOS) transistors and integrated circuits, the latter principally by photolithography and often on printed circuit boards.[citation needed]
Circuit boards are assembled largely using surface-mount technology, which typically involves the automated placement of electronic parts on circuit boards using pick-and-place machines. Surface-mount technology and pick-and-place machines make it possible to assemble large numbers of circuit boards at high speed.
The industry's size, the use of toxic materials, and the difficulty of recycling have led to a series of problems with electronic waste. International regulation and environmental legislation have been developed to address the issues.[citation needed]
The electronics industry consists of various sectors. The central driving force behind the entire electronics industry is the semiconductor industry sector,[1] which has annual sales of over $481 billion as of 2018.[2]