https://www.techradar.com/news/windows-10-october-2018-update-supports-ray-tracing-to-make-games-look-better-than-ever

Microsoft has unleashed the October 2018 Update on the world, bringing plenty of new features to Windows 10, but perhaps the most exciting one for gamers – at least those who have bought one of Nvidia’s new GeForce RTX graphics cards – is the introduction of support for ray tracing to the OS.

Specifically, the big update introduces the first public support for Microsoft DirectX Raytracing (known as DXR for short). This means Windows 10 PCs with the October 2018 Update installed are now capable of supporting real-time ray tracing – as opposed to pre-rendered sequences – providing their GPU also supports this tech.