*Instead of developers having to use thousands of tricks, filters, shortcuts, and post-processing algorithms very carefully arranged and stacked, ray tracing simulates light waves to arrive at the same end result the same way the world actually works.
Ultimately, ray tracing will mean the vast simplification (and therefore cost reduction) of the way visuals in games are produced. Which I'd wager is why it's being pushed so hard.
Basically, a scene in a game has a bunch of objects in it.
It's not to hard to just light them, but it doesn't look that good. Most games want to have shadows, reflections, that sort of thing.
The traditional approach is to use a bunch of extra manual work by pre-calculating a bunch of stuff.
Ray tracing works by simulating how physical photons bounce around in real life. It's existed for a long time; they've used it in animated movies for decades.
The issue with games is that we haven't had hardware capable of doing it in real time until quite recently.
Edit:
That is to say, if you want to animate water or a mirror with ray tracing, you know where the camera is in the scene, and you know where the water/mirror is, so you know the angle the reflection would have come from. So you bounce the photon back that way til you get to the light source.
Sure not going to argue. Though it is still drawing on computing power much how ai does which is the point of the post pointing out how it drives hard on gaming boxes.
Although in this case Nvidia's ray-tracing does actually utilize AI. Both for image upscaling as well as (iirc) optimizing the number of rays needed to be cast for a mostly accurate image.