Derived originally from the agricultural billhook, the bill consisted of a hooked chopping blade with several pointed projections mounted on a staff. The end of the cutting blade curves forward to form a hook, which is the bill's distinguishing characteristic. In addition, the blade almost universally had one pronounced spike straight off the top like a spear head, and also a hook or spike mounted on the reverse side of the blade. There were many types of bill. English bills tended to be relatively short, with broad chopping heads, while Italian bills (ronche) often had very long thrusting points. The English distinguished between several varieties of bill, including the black, brown and forest bills, but the differences between them are currently not fully understood.