Recycling is an activity you can perform within your camp.

"What's more important when you want to survive than making your own tools? But firstly you must learn how to make them! Hence, you'll be able to recycle everything you find, by clicking on your iron coffer. The more you recycle the same object, the more you'll learn how to do it, and then unlock the ultimate recipe to reproduce it. Beware though! Will you prefer recycling a weapon over using it? Choose well."[1]