Fingerprint recognition is based on two facts:




1.Fingerprints never change Small ridges form on a person’s hands and feet before they are born and do not change throughout the person’s life.
2.No two fingerprints are the same In the over 140 years that fingerprints have been routinely compared world wide, no two areas of friction skin on any two persons (including identical twins) have been found to contain the same individual characteristics in the same unit relationship. The ridges on the hands and feet of all persons have three characteristics (ridge endings, bifurcations and dots) that appear in combinations that are never repeated in any two persons.Fingerprint technology has a matching characteristic of 1:1 or 1:N. It has a strong combination of accuracy, speed and ease of use. However, a small percentages of people may not be able to enroll and changes over time in the fingerprint will affect the overall accuracy.

Fingerprint Authentication Procedures:
1.Enrolment: capturing a fingerprint image. An image of the fingerprint in question is created using a fingerprint sensor. The requirements on image size and precision depend on how much information is needed for a proper identification.
2.Extraction: removal of redundant information. The characteristic traits are extracted from the image and all unnecessary information is removed. The more unique this information becomes, the more secure the identification will be.
3.Matching: comparison with stored template.
4.Verification: Comparison of the input image with the image stored that represenets an individual.
5.Identification: Comparison of the input image with all templates in a database
While not quite as accurate as some other biometric technologies, fingerprint recognition is the easiest and most affordable technology to implement. For these reasons it is the most widely used.