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Throughout a home, you probably have several different types of locks. Some that require keys to open, others that turn a knob to lock. The obvious difference is that one takes a key to lock and unlock, while the other locks with a turn of a knob. With so many locks, it is hard to imagine that each key opens a different lock. But, if you know the basic mechanisms behind a key lock, you would understand why. While it is a simple concept and design, it is complex to mimic with something other than the right key. This is why locks are hard to break into. Locks have been protecting our valuables for years. Here is how a key lock works.

A small cylinder houses all the parts. These parts fit into your door. When the lock is open, a piece called the tang is inside the cylinder. When the lock is locked, the tang shoots out, attaching itself to the wall. The tang only opens when something called the shear line, lines up.

Inside this cylinder, there are tiny notches with several springs inside.
Below these springs are 2 pins. The top pins are all the same length. But, the bottom pins are all different heights. So, in order to make the pins line up on the shear line, something must push the bottom pins up. What is the only thing that can push the pins up, all at different heights? You guessed it. A key. So, when the key is in place, all the bottom pins line up, so their top, is along the shear line. This makes the top pins align so their bottoms are along the shear line. And, when the shear line is straight, the tang pops open.

It might sound complicated, but this simple gadget has been working for years. The mechanism works so well, people use it everywhere to protect their valuables inside their homes and businesses. Because the key has to fix just right, you need to keep them maintained. If they key is damages, worn or dirty, it may not work. Make sure you maintain the lock, and the key to ensure both work properly.