This good selection of drivers is included in the more recent versions of Windows.
Disclaimer: the versions after DirextX 11 are included in Windows 8/Server 2016/10 and there are no stand-alone packages. Updates are available through Windows Update.
DirectX is a selection of drivers provided by Microsoft integrating numerous graphical functions/effects (3D, smoke, lights, etc.) especially for games.
Note: During installation process, uncheck the "install the Bing toolbar" option.
Important : The downloaded file checks on your operating system (Windows 7, 8, Vista or XP, 32 / 64bits) and downloads the appropriate version:
Yes, DirectX is free for download when it is not already included in the version of your Windows.