Details the way that different machines operate. Excavators use levers to assist them in doing their work. The platform of an excavator can move around and the cab is soundproof to protect the driver. Most building machines have two kinds of controls, one for driving and the other is hydraulic to operate rams. Twin rams help the dump truck to dump his load.
Tower cranes use pulleys to lift loads.
If an old building needs to be torn down the wrecking crane is used. The drum of a cement mixer is able to turn in two different directions. It can mix the cement and raise the mouth of the drum to pour the cement down the chute. Some machines that push is the bulldozer, it prepares the land by clearing the ground. Rolling machines use their weight to pave the roads so the cars and trucks do not break up.