Exe Encrypter/Packer

Packers basically serves two pupose
1. Reduce the file size
2. Make the code uninteligible to disassemblers and as such dissude prospective reverser from reversing programmes. This is further extended by use f anti-debuggng tricks
packers when run in right environment like no debuggers serves its pupose by first unpacking or decrypting the code it has crypted/packed and run the exe