Just click on
Edit in the main menu after having marked your world. Choose the button for the backup. Then choose the button to open the backup folder. This folder is in
For example, you can save that to a stick and paste it in the same folder of another installation to restore that world from the Minecraft menu.
This folder has the backup also in local multiplayer mode, and any linked computer saves it there. Thus, you can get the saved world from any member of the game, you do not need to ask the local server admin for this.
If you just want to save the world and open it again somewhere else, or after new installation, loading from
saves folder is enough.
Backing up a mod
Saving only the
saves folder is not enough if you also have a mod to save: you should then save the whole
.minecraft folder, see How to backup and restore your local Minecraft files?.