Excavators are heavy-duty machinery consisting of a boom, bucket (or stick) bucket, and cabin on a rotating platform known as the "house". [1] The house is sitting on a tracked or rolling undercarriage. They are a natural progression from steam paddles and are often mistakenly referred to as power paddles. All the movement and functions of a hydraulic excavator is performed using hydraulic cylinders and hydraulic motors, as well as hydraulic fluid. [2] Due to the linear operation of the hydraulic cylinders, the way they operate is fundamentally different from cable excavators that use winches and steel ropes to carry out the movements.

Excavators are also called diggers, JCBs [4] (a registered name in a generic trademark example), mechanical shovels, or 360-degree excavators (sometimes abbreviated as "360" for short). Crawler excavators are sometimes called "trackhoes" by analogy with diggers. [5] also UK wheeled excavators are sometimes known as "rubber ducks"