Overview of biometrics:

Bios  means "life" and metron means "measure") Biometrics is the study of methods to uniquely identify or verify human identities based upon one or more unique physical or behavioral traits.

Overview of fingerprint biometrics:

Fingerprint based biometrics are automated methods designed to identity or verify human identities based upon the unique valleys and ridges present in a fingerprint.

Overview of an SDK:

A software development kit (SDK or "devkit") is  a set of development tools that enable software developers to create applications specific to a certain framework or system.