Following are the client versions of Windows 8 and 8.1. When upgrading to Windows 8 from an existing Windows operating system via download, Windows 8 retains the same word size. For example, a 32-bit Windows 7 machine will be upgraded to a 32-bit Windows 8 operating system. See Windows 8. Windows 8 The standard Windows 8 version, which runs all previous versions of Windows. Windows 8 Pro The Pro version adds data protection via encryption, remote desktop capability (access your PC remotely) and domain connectivity in company and school networks. Windows 8 Enterprise Volume purchases of Windows 8 Pro sold to large organizations. Windows 8 Media Center Available as an upgrade package. Windows RT Although Windows RT looks and feels just like Windows 8, RT is a tablet-only version of Windows 8 that runs apps written only to run on ARM CPUs rather than x86 CPUs. RT comes pre-installed on tablets. See Windows RT and ARM chips.