An electron is real; a probability is not.

Claude Shannon, the founder of information theory, invented a way to measure 'the amount of information' in a message without defining the word 'information' itself, nor even addressing the question of the meaning of the message.

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

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

If you don't understand something, break it apart; reduce it to its components. Since they are simpler than the whole,you have a much better chance of understanding them; and when you have succeeded in doing that, put the whole thing back together again.

Time has been called God's way of making sure that everything doesn't happen at once. In the same spirit, noise is Nature's way of making sure that we don't find out everything that happens. Noise, in short, is the protector of information.

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