Decompilation means taking a program that has already been made and figuring out how it works. You can think of it like taking apart a toy to see how it was made, except with computer programs.
When someone writes a program, they use a special language called code. This code tells the computer what to do and how to do it. But sometimes people might want to see how a program works even if they don't have the original code. This is where decompilation comes in.
Decompiling a program means turning it from something the computer can understand (code) back into something people can understand (kind of like language). When a program is decompiled, it's like putting the toy back together so you can see how it works.
However, decompilation can be tricky because sometimes parts of the code might be missing or hard to understand. So it takes a lot of skill and knowledge to decompile a program correctly.
In some cases, decompilation is a controversial topic because it can be used to steal other people's code or find security vulnerabilities in programs. But it can also be used for good, like helping developers understand how a program works so they can improve it or create something similar.