Cranes are versatile lifting and transporting mechanisms that are made adaptable to a wide variety of jobs by the attachment of an almost infinite number of specially designed grabs. motor operated jib crane has along jib, or arm that extends several feet from a heavy base. The and keeps the crane from tipping over. The operator turns on the motor to lift or lower the hook the arm is lowered. Thus a jib crane can move a weight to any point around the circumference of the circle .This type is suited for operation that require constant and relatively rapid movement of the crane around the job such as in a factory or storage yard.