Eli5: How can games like minecraft or no mans sky be essentially infinite, yet take up a very small amount of storage?

Question

No mans sky is like 18GB or so on my PS4, yet there are 256 galaxies and literally around 18 quintillion planets. It can be played completely offline too, so it isnt coming from some server somewhere

I understand they’re procedurally generated, so they dont even exist until you pass through that area, but even after playing for countless hours and crossing thousands of miles of landmass, the save file is still extremely small

In: 1323

Answer 1

Bcse No mans Sky was a dogwater cashgrab that used procedurally generated assets and it was marketed as huge, despite being mostly empty.

So, til you get there, it wont exist/generate. Since exploring all planets and/or locations would take a huge amount of time, the game will not get heavier in terms of memory space usage unless you spend 20K hours( hyperbolic example).