What you need to know

What are they and how they work

A microprocessor works by inputs, outputs and memory, it consists of a control unit, registers and the ALU, which does the maths for the computer.
Microprocessors have become the movers and shakers of our everyday world. We use them in computers, televisions, watches, microwaves and practically every other electronic device. Their micro-size is no reflection of the myriad capabilities these chips possess, ranging from 2 to 3 mm square to maybe an inch thick. Silicon makes up the material of a microprocessor chip. Sliced wafer thin, silicon serves as an ideal conductor and insulator for transmitting electrical currents throughout the components of the chip. The finished product is an integrated circuit composed of layers of built-in wiring and transistors. Through the use of laser light, circuit outlines are etched onto a silicon surface through a mask or stencil design. A simple chip can have as many as 3,000 transistors, with as narrow a spacing of 60 nanometers between each one.

How they are made

Microprocessor architecture defines the layout of the microprocessor, like a road map. If you have ever seen a PCB (Printed Circuit Board) you will know that it has many tracks leading to different places. Microprocessor architecture is split into two categories: CISC & RISC.CISC stands for complex instruction set computer and RISC for reduced instruction set computer. As the name suggests. CISC is more complex than RISC and is thus able to handle much more complex command, whilst the simpler RISC is faster.


Processor speed is measured as instructions per second (IPS). It represents maximum instruction rates on sequences with few branches, while more realistic workloads lead to lower IPS values. The performance of the memory also affects the processor’s performance, but this is an issue rarely considered in IPS calculations. Because of these problems, researchers have created tests such as SPECint to attempt to measure the real performance in commonly used applications, and raw IPS is no longer used.

IPS is usually measured in thousand instructions per second (kIPS), million instructions per second (MIPS), Giga instructions per second (GIPS), or Million Operations per Second (MOPS). These all measure the processor clock speed.


The first sold microprocessor was the intel 4004 in 1971. It was good for its time and was a huge step in computing. Intel however did not create CPU a man called Frederico Faggin who created it and led the project did. Compared to processors now it is not very good but most great inventions have a humble begining!