In its most basic form a computer is any device, which aids humans in performing various kinds of computations or calculations. In that respect the earliest computer was the abacus, used to perform basic arithmetic operations.
The computer as we know it today had its beginning with a 19th century English mathematics professor name Charles Babbage. He designed the Analytical Engine and it was this design that the basic framework of the computers of today are based on.
Generally, computers can be classified into 3 generations:
* First generation 1937-1946
* First electronic digital computer was built by Dr. John V. Atanasoff and Clifford Berry, called Atanasoff-Berry Computer (ABC) * Computers of this generation could only perform single task and had no operating system. * Second generation 1947- 1962
* Programming languages were developed.
* Computers had memory and operating systems.
* Third generation 1963- present
* Invention of integrated circuit
I. What is a Computer?
A computer is an electronic device, operating under the control of instructions stored in its own memory, that can accept data, process the data according to specified rules, produce results and store the results for future use.
Data and Information
Computers process data into information. Data is a collection of unprocessed items, which can include text numbers images, audio, and video. Information conveys meaning and is useful to people.
Many daily activities either involve the use of or depend on information from a computer A computer processes data into information. In this simplified example, the item ordered, item price, quantity ordered and amount received all represent data. The computer processes the data to produce the cash register receipt (information).
II. The Components of a Computer
A computer contains many electric, electronic and mechanical components known as hardware. These components include input devices, output devices, a system unit, storage devices, and communications devices. Figure 3 shows some common computer hardware components.
An input device is any hardware component that allows you to enter data and instructions into a computer. Five widely used input devices are the keyboard, mouse, microphone, scanner and Web cams.
A computer keyboard contains keys you press to enter data into the computer. For security purposes, some keyboards include a fingerprint reader, which allows you to work with the computer only if your fingerprint is recognized.
A mouse is a small handheld device. With the mouse, you control movement of a small symbol on the screen, called the pointer, and you make selections from the screen,
A microphone allows you to speak into the computer. A scanner converts printed material (such as text and pictures) into a form the computer can use.
A Web cam is a digital video camera that allows you to create movies or take pictures and store them on the computer instead of on tape or film.
An output device is any hardware component that conveys information to one or more people. Three commonly used output devices are a printer, a monitor, and speakers.
A printer produces text and graphics on a physical medium such as paper. A monitor displays text, graphics, and videos on a screen. Speakers allow you to hear music, voice and other audio (sounds).
The system unit is a cast that contains the electronic components of the computer that are used to process data. The circuitry of the system unit usually is part of or is connected to a circuit board called the motherboard.
Two main components on the motherboard are the processor and memory. The processor also called a CPU (central processing unit), is the electronic component that interprets and carries out the basic instructions that operate the computer. Memory consists of electronic components that...