Ever wonderderd what Biometrics are? Do you know how and why biometrics are used? The use of biometric systems and devices for identification and authentication purposes is part of modern day living and is something many people come into contact with on a regular basis. Such systems and devices are used to gain access to a system, such as a secure area. This book contains details of biometric systems and devices used for this purpose, and provides basic general information on how many of them work along with details some of the concerns people have with using these processes.