The World
One world, kept for years.
A 40,000 block Overworld, a permanent Nether and End, and a rotating Resource World for the heavy work.
The map is still being drawn
A live map of the Overworld arrives once Dynmap is rendering. Until then, the best map is your own.
The First Sanctuary
Spawn. Safe, quiet, and where you return to when you type /spawn.
The Overworld
Permanent. Never reset. Build where you like inside the border and claim what you use.
The Resource World
Disposable and regenerated on a schedule. Strip it bare with a clear conscience.