Reverse engineer

Question

How to reverse engineer a software/program?
What does it require?
I downloaded a few programs from websites but I am not satisfy with the way it is so I just wanna edit the program but how?

Answer 1

The first step is to know exactly how the existing program actually works. What any interaction you do gets the program to do. Then, what changes you'd make can be factored into your design. This gives your goals and you code it like you would any other program you choose to write. This assumes you have the skills needed to do this program. If not, you must learn them before starting.