Very Interesting thread here, I was vaguely aware of 3d printers but really didn't know much more than it was a way to make 3 dimensional items. In my extremely limited knowledge, I had no idea it was even something the "average Jane or Joe" could do. So as a result of this thread, off to Mr Google and did a search about 3D printing. !
Here is a link to a site I found that tells you basically what 3D printing is and how it has been used for a really long time in some areas of manufacturing and is headed to be a $41 billion in just 6 years. And so much more of how it is used today.
Thought those of you like me (kinda clueless) might find it interesting. Not something I am inclined to try myself at this point in my life but good to know it is out there in case my wants/needs change.
Murphy
https://3dprinting.com/what-is-3d-printing/