According to Wikipedia, biorhythms are cycles in physiological, emotional, and intellection well-being or prowess. "Bio" pertains to life and "rhythm" pertains to the flow with regular movement.
The theory of biorhythms claims that one's life is affected by rhythmic biological cycles, and seeks to make predictions regarding these cycles and the personal ease of carrying out tasks related to the cycles. These inherent rhythms are said to control or initiate various biological processes and are classically composed of three cyclic rhythms that are said to govern human behavior and demonstrate innate periodicity in natural physiological change: the physical, the emotional, and the intellectual (or mental) cycles.
BioChart keeps your Biorhythms (and those of your friends, significant others, and anyone else) right at your fingertips.