Some devices might include a graphics processor that supports DirectX 9. Some games and programs might require DirectX 10 to provide superior performance and graphics.
Some Windows 8 features, such as touch and snapping apps side by side, might require advanced or additional hardware.
Windows Media Center isn't included in Windows 8. A Windows Media Center license must be purchased separately. DVR functionality might require additional hardware and isn't available in all countries. DVD codecs aren't included in Windows 8. Watching DVDs with Windows 8 requires separate playback software.
The following features are available only in Windows 8 Pro and Windows 8 Enterprise:
BitLocker and BitLocker To Go
Remote Desktop Host
Connect to a network projector
Network location aware services
For more info about Windows 8, see Upgrading to Windows 8.