How Lock Picking Works

Most people carry five to 10 keys with them whenever they go out. On your key ring you mighthave several keys for the house, one or two more for the car and a few for the office or a friend's house. Your key ring is a clear demonstration of just how ubiquitous lock technology is: You probably interact with locks dozens of times every week.
The main reason we use locks everywhere is that they provide us with a sense of security. But in movies and on television, spies, detectives and burglars can open a lock very easily,sometimes using only a couple of paper clips. This is a sobering thought, to say the least: Is it really possible for someone to open a lock so easily?
In this article, we'll look at the very real practice of lock picking, exploring the fascinating technology of locks and keys in the process
Keys are one of the most basic and essential machines we use every day.

Master Keys

Master keys are an interesting technology somewhat related to lock picking (because they're means of getting past locks without the main key). Some locks are designed to work with two different keys. The change key will open only that specific lock, while the master key will open that lock and several others in a group. In these locks, a few of the pin pairs are separated by a third pin called a master wafer or spacer.
When three pins are combined in a shaft, there are two ways to position the pins so theyopen the lock. The change key might raise the pins so that the shear line is just above the top of the master wafer, while the master key would raise the pins so the shear line is at the bottom of the master wafer. In both cases, there is a gap at the shear line and the key is able to turn.
In this lock design, the lowest pin would be the same length in each lock in the group, but the master wafer would vary in length. This lets one person, say a building manager, access many different locks, while each individual key-holder can open only his or her own lock.

Right Key and Wrong Key
As we saw in the last section, a basic cylinder lock is like a puzzle that the correct key can solve very easily. Here's how it works: When you insert a key, the series of notches in the key push the pin pairs up to different levels. The incorrect key will push the pins so that most of the top pins are still partly in the plug and partly in the housing, like this.