The picnic table shown below can be manufactured as a single item or through batch production if hundreds / thousands are required. This is achieved through Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM).

The CNC machine seen below is controlled by the computer. The design has been drawn on CAD software. The drawing is converted by the software to coordinates and transferred to the CNC. The CNC machine then cuts out the shapes of the table top and four legs automatically.
When the first set of shapes are cut, they can be removed from the machine and a new piece positioned for cutting. Each piece cut on the CNC machine will be exactly the same. The process of cutting new pieces can repeated hundreds and thousands of times.

The router is guided around the shapes of the table top and legs by the computer. The shapes are cut efficiently.

When cut to size and table parts are removed and replaced with a new piece of material and the machine is allowed to cut out the next set of table parts.