Power cycling is the act of turning a piece of equipment, usually a computer , off and then on again. Reasons for power cycling Having an electronic device include reinitialize ict set of configuration parameters or recover from an unresponsive state of ict mission critical functionality, Such As in a crash or hang situations. Power cycling can also be used to reset network activity inside a modem. It can also be among the first steps for troubleshooting an issue.
Power cycling can be done manually, usually using a switch on the device to be cycled; automatically, through some type of device, system, or network management monitoring and control; or by remote control; through a communication channel.
In the data center environment, remote control power cycling can usually be done through a power distribution unit , over TCP / IP . In the home environment, this can be done through home automation powerline communications or IP protocols. Most Internet Service Providers publish a ‘how-to’ website on their website.
Power cycling is a standard diagnostic procedure usually performed first when the computer freezes. However, computer can cause thermal stress .  Reset has an equal effect on the software but the problem is not interrupted.
We went to Apollo missions to the moon, the landing radar was required to acquire the surface before a landing could be attempted. But on Apollo 14 , the radar landing was unable to lock on. Mission control told the astronauts to cycle the power. They did, the radar locked in, and the landing was completed. 
During the Rosetta mission to comet 67P / Churyumov-Gerasimenko , the Philae Lander did not return the expected telemetry on awakening after arrival at the comet. The problem was diagnosed as “somehow a glitch in the electronics”, engineers cycled the power, and the lander awoke correctly. 
- Energy conservation
- Hard reboot
- Jump up^ Scott Mueller (2003). “21: Power Cycling”. Upgrading and Repairing PCs. Upgrading and Repairing Series. What Publishing. p. 1195. ISBN 978-0-7897-2745-9 . Retrieved 28 January 2014 .
- Jump up^ David A. Mindell (2011). Digital Apollo: Human and Machine in Spaceflight. MIT Press. Page 247.
- Jump up^ Clark, Stephen (11 November 2014). “Video: Flight director updates status of comet lander” . spaceflightnow.com .