ASPack is an advanced Win32 executable file compressor, capable of reducing the file size of 32-bit Windows programs by as much as 70%. (ASPack's compression ratio improves upon the industry-standard zip file format by as much as 10-20%.) ASPack makes Windows 95/98/NT programs and libraries smaller, and decrease load times across networks, and download times from the internet; it also protects programs against reverse engineering by non-professional hackers. Programs compressed with ASPack are self-contained and run exactly as before, with no runtime performance penalties.