A lock combination is a specific sequence of numbers or symbols used to unlock a combination lock. These locks often have rotating dials or keypads, and the user must input the correct combination to gain access. Commonly found on safes, lockers, and bike locks, combination locks provide a secure way to protect valuables. To set a combination, the user typically selects a series of numbers, which can be changed as needed. The security of a combination lock depends on the complexity and length of the combination. Longer and more random combinations are generally harder to guess, enhancing the lock's security.