"Enterprises face problems end users do not see, however, such as having to keep legacy or custom 16-bit applications running. Windows 8 is similar to Windows 7 in this regard: The 64-bit edition of Windows 8 will only run 64- and 32-bit apps, while the 32-bit edition of Windows 8 will be able to run 32- and 16-bit apps. Note that the ARM version of Windows 8 (aka Windows RT), shipped as a preload with certain devices, won't run anything except software compiled for ARM."