The Friction Stir Spot Welding (FSSW) process is a derivative of the friction stir welding (FSW) process, without lateral movement of the tool during the welding process. It has been used in the production of aluminum doors, engine hoods, and decklids in the Japanese automotive industry. It has the benefits of operation and investment cost savings, weight reduction, high repeatability and consistence, low maintenance, better work environment and recycleability vs. other aluminum spot joining methods such as resistance spot welding (RSW) and riveting. This paper provides a comprehensive literature review of the technology, including joining mechanisms, process controls, process parameter development, fracture behaviors, metallurgy, temperature, tool geometry, and material flow. Variations of the process, joining of aluminum to steel, steel to steel, magnesium, weldbonding (with adhesive), process simulation, and industrial applications are also discussed.