DOSBox is a free and useful DOS-emulator which uses the SDL-library that makes DOSBox very easy to port to different platforms.DOSBox also emulates CPU:286/386 realmode/protected mode, Directory FileSystem/ XMS/ EMS, Tandy/ Hercules/ CGA/ EGA/ VGA/ VESA graphics, a SoundBlaster/ Gravis Ultra Sound card for excellent sound compatibility with older games
