Bis forBarbed wire

Barbed wire, or barb wire, is a type of wire usually used for fencing that has twists of sharp wire along its length. Barbed wire is most often used on fences that keep livestock like cows and sheep from escaping. The sharp barbs on the wire will hurt anything that tries to climb over it.
Barbed wire is not just used to keep animals in or out. Barbed wire was used extensively during war time to protect soldiers, and is also used around prisons to keep the prisoners in.