A backhoe—also called rear actor or back actor—is a type of excavating equipment, or digger, consisting of a digging bucket on the end of a two-part articulated arm. It is typically mounted on the back of a tractor or front loader, the latter forming a "backhoe loader" (a US term, but known as a "JCB" in Ireland and the UK). The section of the arm closest to the vehicle is known as the boom, while the section that carries the bucket is known as the dipper (or dipper-stick), both terms derived from steam shovels. The boom, which is the long piece of the backhoe arm attached to the tractor through a pivot called the king-post, is located closest to the cab. It allows the arm to pivot left and right, typically through a range of 180 to 200 degrees, and also enables lifting and lowering movements. The term "backhoe" refers to the action of the bucket, not its location on the vehicle. That is, a backhoe digs by drawing earth backwards, rather than lifting it with a forward motion like a person shovelling, a steam shovel, or a bulldozer. The buckets on some backhoes may be reconfigured facing forward, making them "hoes". A tractor-loader backhoe (TLB) is a tractor-like vehicle with a backhoe at the rear, a front loader on the other and a swivelling seat to position the operator facing whichever direction is needed at the time. In North America, this arrangement is often referred to as simply a backhoe, or when on a chassis originally derived from farm tractors, a tractor-loader backhoe. To differentiate, a backhoe on its own dedicated chassis may then be referred to as an excavator. Backhoe loaders can be designed and manufactured from the start as such, or can be the result of a farm tractor equipped with a front end loader (FEL) and rear backhoe. Though similar looking, the purpose-designed backhoe loaders are much stronger, with the farm variation unsuitable for heavy work. With the advent of hydraulic powered attachments such as a tiltrotator, breaker, a grapple or an auger, the backhoe is frequently used in many applications other than excavation and with the tiltrotator attachment serves as an effective tool carrier.