Smith machine is a type of weight training equipment that consists of a barbell held within a steel rail, allowing only vertical movement. It is commonly used for exercises such as squats, bench presses, and shoulder presses. Smith machines provide guided motion for the workout, helping with formation and stability, especially for beginners or those recovering from an injury.

However, this also means that the machine may limit some aspects of your workout, such as range of motion, which can lead to muscle imbalances if you rely too much on the machine. Overall, the Smith machine can be a useful tool in a fitness routine, but it should not be the only equipment used and should be balanced with free weights and other training methods.