To be clear, I’m not just arbitrarily designating every component of a car to be a technology. These sub-technologies have lives of their own outside of automobiles. Internal combustion engines are used in some airplanes and electric generators, fans are used for cooling other things besides engines, and nuts and washers have innumerable uses. What’s more, these sub-technologies existed before the car was invented. The car is a collection of these technologies that is put together in just the right way. This is true in general – think of the smartphone (touchscreen, camera, processor) or the electric grid (power plants, transmission wires, transformers).

Zoom in far enough on any technology and you will get down to components that cannot be further dissected. These basic technologies harness some phenomena directly. Phenomena are reliable characteristic of the world we live in. They can be formal and scientific such as Newton’s Third Law (the basis for rocket propulsion), but often they are more colloquial, based on experience, and not necessarily understood at a fundamental level. “Spear tips made of a certain material can penetrate enemy armor” is sufficient, as well as “burning wood produces heat and light”. One of the phenomena that a car engine is based on is that hot gas will expand and drive a piston. A car chassis harnesses the phenomena that steel is strong and rigid.

Putting this all together, technology is modular and recursive. Technologies are built out of other technologies. These technologies can themselves be composed of yet more technologies, and so on. At the bottom of any of these branches is a basic technology that directly harnesses phenomena.

This structure is abstract, but it’s profoundly useful in understanding what technology is and how it changes over time. For example, one reason that technology grows so much over time is that today’s inventions provide the raw material for new combinations in the future. It also sheds light on the process of invention. I will write more about this later, but the main idea is that invention is a process of creatively combining existing technologies, rather than producing something whole cloth.