In today's globally connected world there is increasing interest in using biometrics (personal physical attributes such as fingerprints, facial images, voice patterns, iris codes, and hand geometry) for human verification, identification, and "screening" applications. Biometrics are attractive because they cannot be "forgotten," are not easily stolen, and provide a direct, undeniable link between a user and a transaction. This is a complete technical guide aimed at presenting the core ideas that underlie the area of biometrics. It explains the definition and measurement of performance and examines the factors involved in choosing between different biometrics. It also delves into practical applications and covers a number of topics critical for successful system integration. These include recognition accuracy, total cost of ownership, acquisition and processing speed, intrinsic and system security, privacy and legal requirements, and user acceptance. Features & Benefits: State-of-the-art coverage of biometric theory, research, and implementation Provides a broad orientation for a wide class of readers, yet has tightly integrated topical organization Debunks myths and candidly confronts problems associated with biometrics research Details relevant issues in choosing between biometrics, as well as defining and measuring performance Defines and explains how to measure the performance of both verification and identification systems Addresses challenges in managing tradeoffs between security and convenience This up-to-date and detailed resource is an extensive survey of the principles, methods, and technologies used in biometric authentication systems. Security and financial administrators, computer science professionals, and biometric systems developers will all benefit from an enhanced understanding of this important technology.