DevSlp or DevSleep is a feature in some SATA devices which allows them to go into a low power "device sleep" mode when sent the appropriate signal, which uses one or two orders of magnitude less power than a traditional idle. The feature was introduced by SanDisk in a partnership with Intel. Some think that the initiative could make laptops feel like they power on basically instantaneously, while others state that this means that laptops can stay on all the time, and always be available with no adverse effects on battery life.