A bump key is a specially modified key designed to open pin tumbler locks, which are commonly used in residential and commercial properties. By using a bump key, a person can exploit the lock's mechanism, causing the pins to jump and allowing the lock to turn without the original key. This technique is often associated with lock picking and is considered a method of unauthorized entry. Bump keys are typically created from standard keys by cutting them down to a uniform height, making them compatible with various locks. While they can be used for legitimate purposes, such as locksmithing, they are also associated with criminal activity, raising concerns about security and the effectiveness of traditional locks.