REM stages and one REM stage. Ideally, you repeatedly cycle through each stage. Learn how long each stage lasts.

Circadian rhythms are the cycles that tell the body when to sleep, wake, and eat—the biological and psychological processes that oscillate in predictable patterns each day. This internal clock ...

and wake times can automatically trigger the computer to wake up from sleep. You may select it to check only at Windows startup. Click OK/Apply/Exit. Wake timers are in-built tools in your system ...