1. A method of identifying a living entity comprising: detecting a naturally occurring, internally generated and emitted signal of an individual; resolving the detected naturally occurring, internally generated and emitted signal of an individual into a base and harmonic frequency spectrum comprising a base frequency thereof and a plurality of harmonics of the base frequency; and sampling enough points in the base frequency and harmonic frequency spectrum as resolved for formulating a USN (Unique Signature Number)for a living entity.