Barbed wire, also known as barb wire, occasionally corrupted as bobbed wire or bob wire, is a type of steel fencing wire constructed with sharp edges or points arranged at intervals along the strands. It is used to construct inexpensive fences and is used atop walls surrounding secured property. It is also a major feature of the fortifications in trench warfare (as a wire obstacle).
A person or animal trying to pass through or over barbed wire will suffer discomfort and possibly injury (this is especially true if the fence is also electric). Barbed wire fencing requires only fence posts, wire, and fixing devices such as staples. It is simple to construct and quick to erect, even by an unskilled person.