A computer is a fast, electronic, and computational device, which operates under the control of instructions that can store, send, and interpret data. The first ones produced somehow resemble the modern day computers and were introduced in the middle of the 20th century particularly in the 1940s.

The concept of various machines is slightly similar to the computers that existed much earlier than the said date. The early model of electronic computers was about the size of a very large room that consumes enough power to about 700 modern personal computers.

On the other hand, our computers are now based on integrated circuits. These are a million times more capable while only occupying a small space. Nowadays, computers may be built small enough to fit inside the timepiece. The battery is enough to make it work. Personal computers are also called “icons of the Information Era” and sometimes mistaken to be a computer although the most common computer today is what we call “the embedded computer.”

As the word “embedded” implies, this type of computer is a simple and very small device used in order to control devices. Furthermore, embedded computers are found in machines such as fighter aircrafts, digital cameras, industrial robots, as well as children's toys.

Computers are versatile for they have the ability to execute as well as store instructions, which are called programs. It is said that any computer is probably capable in performing the tasks that any other type of computer can do. So it means that any type whether it is a personal or a super computer, are able to do the same computational tasks that are presented or given to them given that they have enough storage capacity.

How Does a Computer Work?

In general, ithas four sections namely the control unit, the ALU or arithmetic and logic unit, and the I/O or the input and output devices. Groups of wires called “busses” interconnect all the parts.

The ALU, control unit as well as the basic input and output devices along with other hardware that are closely linked with the said devices are known as the CPU or the central processing unit. The early versions of CPU were made of various separate components but ever since the 1970s, the CPUs are typically constructed on a sole integrated circuit known as a microprocessor.

The Control Unit is also called a central controller and control system that directs other computer components. Its main process is to decode or interpret one by one the set of instructions in a program. It decodes each set of instruction and turns them into a sequence of controlled signals that functions the computer parts. The control systems of advanced computers may probably change some of the order of the instructions in order to improve its performance.

A main component of all CPUs is the special memory cell or a register called the “program counter”. The so-called program counter keeps track of the location of the memory wherein the next set of instructions is read.

The control system has various functions. One of which is to read the code of the next set of instructions from the indicated cell of the program counter. Another function is that it decodes the numerical codes of the instructions into a series of signals or commands for each system.