Combination lock – Simple English Wikipedia, the free encyclopedia

Mechanical combination lock
– Consists of three discs inside
– Last disc connected to the dial
– Notch on last disc rotates second disc
– Notch on second disc rotates first disc
– Popular on safes and padlocks

Electronic keypad lock
– Uses keypad similar to a telephone keypad
Combination entered one number at a time
– Motor opens the lock when correct combination is entered
– Popular on safes and doors, not on padlocks
– Requires batteries or another source of electricity

– Cannot be picked (without key backup)
– No need to carry a key
– Little chance of getting locked out if combination is remembered
– User can set the combination
– Popular on safes and doors

– Mechanical combination locks can be difficult for first-time users
– Batteries can die in electronic locks, preventing opening
– Combination can be obtained by watching a legitimate user
– Combination can sometimes be guessed based on wear on buttons
– Time-consuming and frustrating if combination is forgotten

Other considerations
– Limited number of possible combinations can make locks easier to crack
– Vulnerable to brute force attacks if correct sequence is known
– Not suitable for high-security situations with severe consequences
– Some locks have key backup, which can be picked
– More modern keypad locks have additional buttons to prevent wear marksSources: