[quote name='Telios' timestamp='1341425643' post='4955682']
Direct3D 9 supports Xbox360 and Windows XP, whereas D3D11 does not.
Direct3D 11 supports Windows Vista onwards only, but can run on earlier D3D9-level hardware using feature levels.
Ok, that;s clear, but does Direct3D 9 support Vista and Windows 7 ? In other words, can someone install DirectX 9.0 SDK on Windows 7 and develop a game that will run on WinXp to Win 7 and above ?
[/quote]
Sure, as long as your target machine has the required runtimes installed.
And there's no such thing as the DirectX 9.0 SDK, all current versions of DirectX (including 9) are bundled together in the DirectX SDK (which is now part of the Windows SDK)