Identification and authentication requirement are steadily increasing in both the online and offline worlds. The biometric is increasingly viewed as the ultimate form of authentication or identification, supplying the third and final element of proof of identity. Accordingly, it is being rolled out in many security application. The safety and reliability patterns inherent in Aviation are built on human skills and sense of personal responsibility, aided by modern sophisticated equipment that must be well maintained and capably used. This book will be useful to all Aviation personnel and students in tertiary institutions pursuing degree or diploma courses in Aviation, Information Technology, Telecommunications and Management.