System Management Controller

The System Management Controller is a subsystem of Intel Macintosh computers and Apple silicon based computers. It is similar in function to the older System [Management Unit|SMU] or PMU of PowerPC based Macintosh computers.

Overview

The SMC has roles in controlling thermal and power management, battery charging, fan control, Motion detector, Light sensor, sleep and wake, hibernation, and LED indicators. It also enables enforcement of the macOS End User License, allowing macOS to identify when it is running on non-Apple hardware.
SMC uses ACPI on Intel Macs and on Apple silicon based Macs for communication.