A look into why power management is needed and required for Linux. Obvious applications of power management is in the laptop space but many other uses of Linux require power management. In addition, the different flavors of Linux management as it is found on common desktop x86 implementations and on embedded applications. Reasons can extend beyond the obvious uses such as battery life. Hunyue Owner HY Research, LLC Embedded Linux consultant, developer and enthusiast almost 20years of involvement in opensource. He has worked on numerous Linux architectures including x86, ARM, and Power PPC. Areas of interest include low power and small foot print Linux for mobile Linux devices with a focus on low level kernel and hardware details.