With the increasing importance of sieges in the Middle Bronze Age, siege tactics were enhanced. One of the innovations was the battering ram, which could break through doors or even walls. It seems to have come in wide use around 2400 BCE. Together with other siege techniques, it remained in use as long as places were defended by walls, i.e. well into the Middle Ages.
The basic design for a battering ram is a thick pole, preferably with a head reinforced by metal. It is hung by ropes or chains from a frame, from where it can be swung back and forth repeatedly. Of course wall defenders would try to counterattack by raining down missiles on the operators of the ram. Therefore many had slanted roofs to let these bounce off and were covered in wet hides to prevent them being set on fire. Battering rams and their canopies were often mounted on a cart, so that they could be constructed at a safe distance and then driven to the walls. Others were so light that they could be carried by a team of operators.
In and around the Middle East, many city walls were built of soft stone or even dried mud, which was vulnerable. Sometimes the besiegers tried not to batter these down, but to scrape parts out, using a 'siege hook' rather than a ram.