This article presents a detailed discussion on the characteristics, types, properties, quenchants, applications, advantages, and disadvantages of various types of quenching: air quenching, water quenching, rinse quenching, time quenching, press quenching, delayed quenching, fluidized-bed quenching, ultrasonic quenching, intercritical quenching, subcritical quenching, ausbay quenching, hot isotactic press quenching, slack quenching, differential quenching, and double quenching.