Figuring out how a program works when that program has been deliberately made difficult to understand
Deobfuscation is the reverse process of obfuscation. It means figuring out how a program works when that program has been deliberately made difficult to understand.
Deobfuscation is related to reverse-engineering. If the question is about reverse engineering rather than programming then posting on the Reverse Engineering site should be considered instead.
Do not use this tag merely to indicate that you don't understand how a program works: use it only when the program was made obfuscated on purpose.