An analogy between information and energy

Information technology is a useful term. We store information and transfer it, all of which is helpful in understanding the information is not matter. However the association with storage capacity means that people may think in terms of size—number of bits—not the nature of what is stored.

This is somewhat analogous to talking about fuel tank capacity. Vehicles need energy to travel and all things being equal a larger fuel tank will supply more energy. But the issue here is energy. If one focuses on fuel tank size he can forget that it matters what is in the fuel tank. Different grades of gasoline contain different amounts of energy, and the same is true for other fuels such as methanol, ethanol, and coal. One can even fill a tank with substances that contain no energy such as sand or water (fusion disregarded). And other forms of energy such as electricity do not even require a petrol tank.

So while fuel tank size can be a proxy for energy, it may be inadequate, or even inappropriate. One must remember that it is energy that is being discussed.