What is a Computer?
A Computer is an electro – mechanical device/machine which accepts data
as input. Processes the data according to a set of previously stored
instructions called program and produces the result as output in form of
information.
Or
A computer
is an electronic device that manipulates information, or "data." It
has the ability to store, retrieve, and process data. You
can use a computer to type documents, send email, and browse the internet. You
can also use it to handle spreadsheets, accounting, database management,
presentations, games, and more.
Computer accepts data as an input through an input device e.g. keyboard
process the data through an output device e.g. monitor/printer.
Computer is defined as an electro – mechanical device/machine because
its principle of operation is based on electronics. Computer is a machine
because like any other machine, a computer requires a steady supply of energy
and skilled personnel for its operation. For instance, the Registers, Counters,
RAM, ROM etc all operate on the principle of electronics. However, the movements
of papers in the printers, the insertions of diskettes from drive are
mechanical.
Data and Information
Data is referred to as raw facts/figure which when processed give us
meaningful information. That is, Data are facts that are yet to be processed
while information is the result obtained from processed data. For instance, the
marks obtained by a particular student in his or her six examination courses
are 30, 60, 65, 70, 80 and 40. These figures are raw facts described as data.
However, if these marks are added together and the total mark and percentage of
the mark scored obtained, then such total and percentage of the mark is the
information obtained from the data.
What are the
Different Types of Computers?
When most
people hear the word "computer" they think of a personal computer
such as a desktop or laptop computer. However, computers come in
many shapes and sizes, and they perform many different functions in our daily
lives. When you withdraw cash from an ATM, buy fuel from a fuel dispenser or
use a calculator, you're using a type of computer.
Desktop Computers
Many people
use desktop computers at work, home, school, or the library. They can be
small, medium, or large in style, and usually sit on a desk. Once you add a
monitor, mouse, and a keyboard, you have what is typically known as a Desktop Computer.
Most desktop computers are easy to upgrade and expand, or add new
parts. Another benefit of desktop computers is the cost. If you compare
a desktop and a laptop with the same features, you will most
likely find that the desktop computer is priced lower.
Some desktop
computers have a built-in monitor to save space. These are often called all-in-one
desktop computers.
Laptop Computers
The second
type of computer that you may be familiar with is a Laptop Computer
or laptops as they are often referred to. Laptops are battery or AC-powered
personal computers that are more portable than desktop computers,
allowing you to use them almost anywhere.
Since a
laptop is smaller than a desktop, it's more difficult to access the internal
components. That means you may not be able to upgrade them as much as a
desktop. However, it's usually possible to add more RAM or a bigger hard
drive. A laptop computer is sometimes called a notebook computer because
of its size.
Servers
A Server
is a computer that "serves up" information to other computers on a
network. Many businesses have file servers that employees can use to
store and share files. A server can look like a regular desktop computer, or it
can be much larger.
Servers also
play an important role in making the internet work: they are where web pages
are stored. When you use your browser to click a link, a web server
delivers the page you requested.
Other Types of Computers
Today, there
lots of everyday devices that are basically specialized computers, even
though we don't always think of them as computers. Here are a few common
examples:
- Tablet Computers: These use a touch-sensitive
screen for typing and navigation. Since they don't require a keyboard
or mouse, tablet computers are even more portable than laptops. The iPad
is an example of a tablet computer.
- Mobile Phones: Many mobile phones can do a
lot of things a computer can do, such as browsing the internet or playing
games. These phones are often called Smartphone.
- Game Consoles: A game console is a
specialized kind of computer that is used for playing video games.
Although they are not as fully-featured as a desktop computer, many newer
consoles, such as the Nintendo Wii, allow you to do non-gaming
tasks like browsing the internet.
- TVs: Many TVs now include applications
(or apps) that let you access various types of online content. For
example, you can view your Facebook news feed or watch streaming
movies on Netflix.