We’ll start with the natural building block of any digital system: the bit. A bit is just a binary digit, a one or a zero. Bits are used to encode information. For example, imagine I have a bunch of red cards and a bunch of green cards. I give a red card to everyone in the country except for the President to whom I give a green one. Since the cards only have two possible states, they are a form of bit. The information associated with that bit, however, is highly complex.
Bits are combined into series to represent larger sets of possibilities. Whereas the President bit could only represent two possibilities: someone is the President (red card) or not the President (green card), a string of n bits can represent 2n possibilities. Almost all digital information in the world today is stored as groups of eight bits called “bytes.”
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