ACPI, or Advanced Configuration and Power Interface, is a standard that helps operating systems manage power consumption in computers. It allows the OS to control the amount of power supplied to various components, such as the CPU, hard drives, and peripherals, optimizing energy use and extending battery life in laptops. Introduced in the late 1990s, ACPI provides features like sleep modes and thermal management. By enabling devices to enter low-power states when not in use, it improves overall efficiency and reduces heat generation, contributing to better performance and longevity of hardware components.