I have recently asked a question about taking God's name in vain. And I have been told that swearing is taking his name in vain. So in teachings I see it mentioned G-d or Gcd. Showing to me a resistance of even saying the word "God". Why is this necessary? For when I say "God" I most likely am not swearing an oath. In Judaism do they believe that writing God's name is swearing an oath?
There are two different issues. 1. Using a specific name of Gd when swearing an oath which is not allowed. 2. Showing respect to any divine name.
This link here, will fully explain the how and why of writing Gd's name. But the short version, is that writing Gd or G-d is in order to show respect to Gd and to not cause the name to be erased, or treated poorly. It's unrelated to not using Gd's name in vain.