RTX GI or RTX for Global Illumination allows for innovative new ways of bringing dynamic lighting to your game. It offers indirect lighting, infinite colored bounces, and soft shadows while being fast and scalable. Check out this video to see how to achieve this.
This is part of a series of Unreal 5 related introductory videos first listed in our technical blog on the developer pages. https://developer.nvidia.com/blog/shaping-the-future-of-graphics-with-nvidia-technologies-in-unreal-engine-5/