The Microprocessor

The Intel 4004 was the very first microprocessor, invented by Ted Hoff in 1969–71 for Busicom,
a  Japanese client of Intel. Since Busicom had financial problems, the order was rejected. The 4004 was then put on sale on 15 November 1971, in the classified advertisements of the magazine Electronic News. Its success was immediate. Computing had just entered a new era.

The microprocessor is the brain of the computer. It is an integrated circuit, a chip specialising in the management of information. It controls the flow of information and performs arithmetic operations,
such as additions, or logical operations, such as comparisons. The microprocessor is so much the centre of the computer that the latter is often defined by the former. For example, a 386/33, a 486, a
Pentium, Cyrix, AMD and Pentium III are all types of microprecessor.

The standard currently sold in the shops is a 64-bit Pentium III microprocessor. The bits in this case describe the simultaneous inputs of the microprocessor data bus. A group of 8 bits constitutes a byte, an octet or a character. The computer uses a binary notation system. Each character, number and symbol is coded into a group of 0s and 1s. Each 0 (off) or 1 (on) is equivalent to a binary digit, also called a bit.

To summarise:
1 bit = 1 binary position
1 byte = 1 character = 8 bits
1 kilobyte (kbyte) = 1024 bytes
1 megabyte (Mbyte) = 1024 × 1024 bytes
1 gigabyte (Gbyte) = 1024 × 1024 × 1024 bytes