The San Andreas Fault (SAF) is one of the most prominent transform faults in the world, stretching over 1,200 km through California, USA. As a major plate boundary between the Pacific Plate and the North American Plate, it plays a critical role in shaping the region's geology and posing significant earthquake hazards. This paper provides an in-depth review of the San Andreas Fault, its geological setting, structural evolution, and implications for earthquake hazard assessment. We also discuss the current state of knowledge on fault mechanics, earthquake triggering, and the potential for future large earthquakes.