https://www.sleepfoundation.org/circadian-rhythm
https://en.wikipedia.org/wiki/Circadian_rhythm
From Wikipedia, the free encyclopedia
A circadian rhythm (/sərˈkeɪdiən/), or circadian cycle, is a natural
oscillation that repeats roughly every 24 hours. Circadian rhythms can
refer to any process that originates within an organism (i.e.,
endogenous)...