Minecraft dimensions
Minecraft generates three dimensions from the same world seed, each with its own rules for terrain, biomes and structures.
The seed map generates each dimension separately. Switching dimension keeps your seed and version but rebuilds the map with that dimension's rules — including the 1:8 coordinate ratio between the Overworld and the Nether.
Overworld
The Overworld is the dimension you spawn in. It holds every surface biome, the cave biomes added in 1.18, and most of the structures in the game.
Coordinates 1:1
Nether
The Nether is a compressed dimension used for fast travel and for resources that do not exist in the Overworld: netherite, blaze rods, nether wart and ancient debris.
Coordinates 1:8 — one Nether block equals eight Overworld blocks
End
The End contains the ender dragon fight on the central island and, beyond a 1000-block gap, thousands of outer islands holding end cities and elytra.
Coordinates 1:1