Numerology is a pseudoscientific belief that numbers and letters have a special meaning about the individual that is not revealed to them. This belief has no scientific basis and has existed only in the western world, primarily in Europe and America, since ancient times.

Numerology has been practiced by various cultures, including the Romans, Egyptians, Chinese, Greek, and Hebrew cultures. It is also practiced by some Native American tribes, such as the Hopi and the Arapaho. It is not practiced by any Native American tribes in the Americas that are not mentioned above.

There is no universal agreement on what numbers and letters mean. However, most people in the western world believe that Biorhythms and the numbers of Numerology have a meaning about the individual. Biorhythms are cycles of physical, emotional, intellectual, and spiritual development. Numerology numbers can be used to describe an individual's personality, physical characteristics, and career.