A bit or binary digit is the smallest unit of information in technical terms. Binary means that there are just two options: true or false, 0 or 1, energy on or off. When some parts of the computer get power, this resembles one condition of the binary digit. If there is no power, the bit equals 0. A bit is just a fraction of a piece of information, and with one single bit there is often no real meaning in it. However, combining bits, data, and messages allows information to be generated, stored, and processed in the computer.
A byte consists of 8 bits. A byte can have 28 = 256 possible values and can be used to represent one single character. Several coding schemes have been created to link a specific pattern of bytes to a letter or word. Using for example ASCII, a very well known standard for character encoding, ‘A’ has the value of 65 or in binary terms 01000001.
The number of bits a computer can process before the central processing unit (CPU) needs to break down the information into smaller parts is a key performance indicator of the computer’s speed. Today’s computers work with 64 bits. The equivalent decimal number, over 18 quintillion digits, is what a processor can process at once.