DirectX is a collection of application programming interfaces (APIs) for handling multimedia, especially game programming and video, on Microsoft platforms. It is a key component of Microsoft Windows and is used by many games and other multimedia applications. To check what version of DirectX you have installed, you can use the DirectX Diagnostic Tool (DXDiag).
To open DXDiag, press the Windows key + R and type “dxdiag” into the Run dialog box. Then, click OK. The DirectX Diagnostic Tool will open and display information about your DirectX version and other system information.