What is decoder?

A decoder is like a special key that turns secret messages into something you can understand.

Imagine you have a toy box full of different toys, cars, blocks, and balls. Each toy has a unique sound when it’s shaken: vroom, clack, boing. Now imagine someone sends you a message made up of these sounds, like "vroom clack boing". Without knowing what each sound means, it's just a bunch of strange noises.

That's where the decoder comes in. It’s like a magic translator, but not magic, just really good at matching sounds to toys. If you tell it "vroom" means a car, "clack" means blocks, and "boing" means a ball, it can turn your message into a list of toys: car, block, ball.

Think of the decoder as a smart friend who knows all the rules. When you give them a secret message, they use their knowledge to figure out what each part means, just like how you know that vroom is your favorite toy's sound!