DOS-based programs (COD, KBX, and FILL): An IBM-compatible computer using DOS 2.0 or higher. A printer is often useful but not required. DOS programs can also be run on Windows 3.1, 95, 98, 2000, Me, and XP.
Windows-based programs (COD, SCG, Medecode, BMK, RAC, and PIN): Windows 3.1, 95, 98, Me, 2000, or XP. A mouse is recommended. If you have a version of COD before August 2002 and want to use it on Windows 2000 or XP, you will need to download a driver.
Disk space: COD requires about 5 meg of space. RAC uses about 3.5 meg. The next largest programs are FILL and KBX Europe, each of which requires about 1 meg of space.