This document summarizes research on face recognition systems and their applications. It first defines face recognition as the process of identifying or verifying a person by analyzing facial patterns and contours. It then discusses the history of face recognition research from the 1960s to modern times. Principal component analysis and eigenfaces were important early milestones. Current applications discussed include access control, security, image database searches, and more. Finally, it outlines common face recognition methods such as holistic matching, feature-based matching, and hybrid approaches.