(This set of courses mainly explains the PE file structure of software encryption and decryption. PE (Portable Execute) files are the general term for executable files under Windows. The common ones are DLL, EXE, OCX, SYS, etc. In fact, whether a file is a PE file or not, no matter what the extension is, PE files can have any extension, and the code in the course will involve C, C++ and other knowledge.)