As software development companies, their biggest concern is that their software will be decompiled/cracked soon after it is launched, so many developers choose to pack/encrypt their software products. In general, the file size of packed software is smaller, and the program itself becomes more secure. These days, packer has been moving towards virtual machine protection technology, whose greatest benefit is that it can greatly improve the protection strength. Packers employing this technology include Themida, WinLicense, EXECryptor, etc.; While the downside is that it affects the startup and running speeds of program, so it's not suitable for every situation.