Master–slave (technology)

Master–slave is a common terminology for a model of asymmetric communication or control where one device or process (the master) controls one or more other devices or processes (the slaves) and serves as their communication hub. In some systems, a master is selected from a group of eligible devices, with the other devices acting in the role of slaves.

Master–slave terminology was first used in 1904. Since the early 21st century, the terms have become a subject of controversy from their association with slavery and some organizations have opted to replace them with alternative terms.