India, Oct. 5 -- You see it daily, but you've probably never really looked at it. That little metal rectangle on your door frame? It's not there to look shiny. It's actually the reason your door closes, locks, and doesn't fall apart. Let's break it down. Also read | Everyday explained: Why do elevators almost always have mirrors? Know the real reason

That metal thing, it has a name. According to a guide published by Doorsandbeyond.com, it is called the strike plate. You know how your door has hinges on one side that let it swing? On the opposite side, where the handle clicks into the frame, there's a flat metal plate screwed into the wood. When you close your door, that latch shoots out and lands right into the hole in that plate.

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