Rinds on the outside of meat, are they safe?

Not sure what the out layer of skin on meat is called, when they slice off into lunch meat it’s the circle around the slice. I normally eat the whole slice of turkey/ham/roast beef and forgot about the brown ring. Is it safe to eat? What is it made of?

from Zero Carb Zebras http://bit.ly/2EWYlIw
via IFTTT