What is the difference between a flat world and a normal world n Minecraft?

So in a flat world, bats do not spawn everywhere and the horizon is not dark even though you are at the height of 3-5. In a normal world, field mice spawn when everything is gone, and the horizon is also dark at 0-63.

How can I convert a normal world as flatworld / change attitude?

Is that stored in the NBT data of the world?

Does anyone know about MinecraftWelten?

The difference between the flat world and the normal world is already in the name: the flat world is flat…

I do not quite understand what you want with bats?
The world type has nothing to do with the spawning of monsters / animals.
They spawn as they should…

No, if you have a flat world, bats do not spawn, but in a normal world, even at low altitude, why is that?

I'm not sure, but it may be because flat worlds have no caves or spaces. Have not seen any bat outside of caves, of course (for example, by digging a very large hole)

No bats do not spawn on top of that. In the normal world, if you do everything at the level of 3-5 Plalts everywhere field mice and the sky / horizon is black.

You can't change the world type after generation. A flatworld is like Endivie02 already said has completely flat and a normal world is generated normal, the animals and mobs spawn in both types completely without differences and that with the bats you can't change, if it is so at all.

I never watched to be honest.

But to be honest I do not know when the sky should turn black.

(Recorded at level 1)

That is stupid

Ok, I think I know what you mean by black. The clouds are only black with me. Not the sky. I think the horizon is black because you either look into nothing or it has something to do with caves

It looks like the world type has a small impact. The black horizon or the sky can also be reproduced on the flat world as soon as you are below the coordinate 0. I assume this has something to do with the value of Sea-Level. You can set that in a world. Just put the world type on "Customized". The first value should be the whole rules

Does each chunk / field have exactly one file with the same name per coordinate? Then you could overwrite chunks vllt