A pin tumbler is a type of locking mechanism commonly used in locks, such as door locks and padlocks. It consists of a cylinder that contains a series of pins of varying lengths. When the correct key is inserted, the pins align at a specific height, allowing the cylinder to turn and unlock the mechanism. This design is widely used due to its simplicity and effectiveness. The security of a pin tumbler lock can be enhanced by using different pin configurations and additional features, making it a popular choice for both residential and commercial applications, including deadbolts and smart locks.