How do they steal, view, copy source codes?

Question

reverse engineering

Let's say I just found a program, an application, some kind of software or a website, well, I just can't understand how you can take it and see it? Without any programs, I just can’t understand it, so let’s say I went to the site opened the source code? Or I downloaded the program, I’ll take a break with me, the program is protected software, here’s how I can see if there is no such Settings, how is it all done in general, tell me experts, thanks to everyone in advance

Answer 1

Reverse engineering and source code theft are two different things.
To get a useful answer to your question, you need to learn how to formulate a question, and you mixed both horses and people into the question.
Wikipedia is quite a good source for reading the definition of various terms. Therefore, look there for what is the source code, and what is reverse engineering.
You can also search "software protection"
lurkmore.to/Reverse_Engineering
https://en.wikipedia.org/wiki/%D0%9E%D0%B1%D1%80%D...
https://en.wikipedia. org/wiki/%D0%98%D1%81%D1%85%D...
https://en.wikipedia.org/wiki/%D0%97%D0%B0%D1%89%D...

Answer 2

In general, there are 2 different things: a program in a compiled language (C/C++/Golang/etc), i.e. source; and a program in one of the CPU languages ​​\u200b\u200b(for GPGPU - GPU), the so-called release version (or debug, but the essence does not change, because there is not much more information in the debug binaries), it then ends up on the computers of clients / software consumers . CPU languages ​​(GPU - especially) there are many. The code for them needs to be translated into IR / IL - a fictitious auxiliary language, then into a C-like functionally equivalentdecompiled code. So you can't get the source, but for mods/cracks/etc it's better than assembler. But the downside is that with such code, dancing with a tambourine may be required before compiling it again. For bytecodes, everything is not so difficult, where the decompiled code often coincides with the source code. For the first (except for the GPU - in development) there is Ghidra, for bytecodes: JVM bytecode - Fernflower / CFR, C # bytecode - JB dotPeek, Python bytecode - Uncompiler. In general, there is no protection in most cases, in fact the whole problem is in the difference between the source code and what the processor is able to understand. So never try to translate CPU (x86/PPC/MIPS/ARM/AARCH64/...) to C++, only to C.