2. Biometrics: where should I start?

‘Biometrics: where should I start?’ considers what constitutes a practical biometric system. It looks at the principles on which such a system operates, builds up a picture of the components needed to construct such a system, and takes the first steps towards understanding how to implement a biometric system. It also looks at how, when, and why errors can arise and how the performance of a biometric system can be evaluated, both qualitatively and quantitatively, to understand more clearly the nature of the interaction between the user and the system itself, and to determine helpful ways of describing both basic system factors and user characteristics, which will ultimately influence system performance.