A home automation system automates your whole house, triggering events and routines involving light fixtures, security components and the heating/cooling system based on the time of day, temperature or any other condition that you select. For instance, when a sensor detects a vehicle in your driveway, your home automation system could turn on your lights.
An automation system controls a collection of "subsystems." A subsystem is a system that—even when operating by itself—provides benefits to a homeowner. Common subsystems include lighting, security, entertainment and heating/cooling systems, as well as devices like motorized drapes and basic appliances. A home automation system puts two or more subsystems under the control of one central controller, so that the press of one button can issue several commands to a variety of different electronic products."

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