Razor wire

Razor wire is like barbed wire, which is like a bunch of sharp points that stick out of a metal fence, except the sharp points on razor wire are much more dangerous. It looks like metal coils with metal blades on the end that are usually very sharp. It's usually used on fences to keep people from getting in or out. It's very hard to climb over or go through because it can be very painful and it can even cut you.