Question about ground detection

What is Ground Check, and why do I need it.

Ground detection is very important in the majority of games as it conveys information that is needed for certain mechanics. This information can be the distance between your character collider and the ground, the normal(which can be used to find the angle as an example), and so on.

When jumping, you most likely want to be standing on ground first, else you could just jump into the sky which to me sounds like a boring game.

Ground detection(or probing) is also useful to separate level geometry into floors and walls(everything not detected as ground is considered a wall, for instance).

Depending on your use cases, the implementation could be a simple raycast, or in cases where very accurate results are needed, you might want to query for triangles inside a given volume(which sadly is supported PhysX but not exposed to Unity, so you would have to roll your own solution).

So… what is your question exactly?