Numbers instill a feeling for the lie of the land, and furnish grist for the mathematical mill that is the physicist's principal tool.

If the intensity of the material world is plotted along the horizontal axis, and the response of the human mind is on the vertical, the relation between the two is represented by the logarithmic curve. Could this rule provide a clue to the relationship between the objective measure of information, and our subjective perception of it?

Information gently but relentlessly drizzles down on us in an invisible, impalpable electric rain.

If quantum communication and quantum computation are to flourish, a new information theory will have to be developed.

As every bookie knows instinctively, a number such as reliability - a qualitative rather than a quantitative measure - is needed to make the valuation of information practically useful.

We don't know what energy is, any more than we know what information is, but as a now robust scientific concept we can describe it in precise mathematical terms, and as a commodity we can measure, market, regulate and tax it.

In order to understand information, we must define it; bit in order to define it, we must first understand it. Where to start?