Biometrics
The study of methods for uniquely recognizing humans based upon one or
more intrinsic physical or behavioral traits.
Fingerprinting:
A fingerprint is an impression of the friction ridges of all or any part of the finger. A friction ridge is a raised portion of the epidermis on the palmar (palm and fingers) or plantar (sole and toes) skin, consisting of one or more connected ridge units of friction ridge skin. These ridges are sometimes known as "dermal ridges" or "dermal papillae".
Definition:
Fingerprint
identification (sometimes referred to as dactyloscopy or palmprint
identification is the process of comparing questioned and known friction
skin ridge impressions from fingers or palms to determine if the impressions
are from the same finger or palm. The flexibility of friction ridge skin
means that no two finger or palm prints are ever exactly alike (never
identical in every detail), even two impressions recorded immediately after
each other. Fingerprint identification (also referred to as
individualization) occurs when an expert (or an expert computer system
operating under threshold scoring rules) determines that two friction ridge
impressions originated from the same finger or palm (or toe, sole) to the
exclusion of all others.

Fingerprints
may be deposited in natural secretions from the eccrine glands present
in friction ridge skin (secretions consisting primarily of water) or
they may be made by ink or other contaminants transferred from the peaks
of friction skin ridges to a relatively smooth surface such as a
fingerprint card.[2] The term fingerprint normally refers to impressions
transferred from the pad on the last joint of fingers and thumbs, though
fingerprint cards also typically record portions of lower joint areas of
the fingers (which are also used to make identifications).