Games : Is there a map editor thats not a mod

Ive played Skyrim on xbox a few times and i really enjoy the scenery. Skyrim being a big puzzle on its own, required me to look up a few things and i sometimes come across posts about a map editor.

My questions are:

• Does Skyrim on pc have a map editor that is not a mod?


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  Does it come with the standard edition or do i need one of the expansions or extra downloads?

  
  


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  And; how much can you really do with a map that you made yourself? (as in; play it, do/create quests, etc..)

  
  

Any information about the subject is welcome, i don't usually play these kind of games on pc.