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 the Microsoft Windows operating system and is used by many games and other multimedia applications.
The latest version of DirectX is 12, which was released in 2015. However, many games and applications still use older versions of DirectX. If you are having problems with a game or application, it may be because you are not using the correct version of DirectX.