Have you wondered how Minecraft can produce massive worlds that are still chock-full of little details, like elaborate cliff faces and waterfalls? PBS' Game/Show is more than happy to explain in a new video. As you'll see below, Mojang's game relies on procedural generation, which automatically creates environments and objects that are at once random, but guided by rules that maintain a consistent logic. Mountains are always rocky and sprinkled with snow, for example, while the low lands are typically full of grass and trees.
Minecraft is specifically using Perlin noise calculations, like the kind you'd use to create a rough-looking texture for a 3D model. It starts out on a very broad level, painting a basic topographical map, and adds "noise" through finer terrain details like lakes, shrubbery and animals. Importantly, it has just enough freedom to create unexpected delights, like the elaborate rock structure you see above -- as in the real world, there's an incentive to discover what's just around the bend.
Procedurally-generated game content certainly isn't new. The Diablo series and Spelunky use it to keep their environments fresh, while Borderlands uses the code to generate one-of-a-kind weapons. The seemingly infinite variety of worlds in the upcoming No Man's Sky would be impossible without it. However, it's safe to say that Minecraft's absolute dependence on this math is what makes it special. Every playthrough can be unique, and there's so much to see and do that it could take a long, long time before you've explored every last nook and cranny.