How do I use junk?

I'm pretty new to this game and probably missing something really obvious, but I can't figure out how to use junk. That microscope would probably be useful in the medical bay, for example. What do I press to make it go?

junk


Solution 1:

Junk is used for crafting, using two new rooms: the Weapon Workshop and the Outfit Workshop.

Once you have found some recipes, and built/upgraded a sufficient level workshop, you can assign dwellers to the room, then access the "craft" button when the occupied room is selected.