Basics of Computers - Classification
Historically
computers were classified according to processor types because development in
processor and processing speeds were the developmental benchmarks. Earliest
computers used vacuum tubes for processing, were huge and broke down
frequently. However, as vacuum tubes were replaced by transistors and then
chips, their size decreased and processing speeds increased manifold.
All
modern computers and computing devices use microprocessors whose speeds and
storage capacities are skyrocketing day by day. The developmental benchmark for
computers is now their size. Computers are now classified on the basis of their
use or size −
- Desktop
- Laptop
- Tablet
- Server
- Mainframe
- Supercomputer
Let us
look at all these types of computers in detail.
Desktop
Desktop computers are personal computers (PCs) designed
for use by an individual at a fixed location. IBM was the first computer to
introduce and popularize use of desktops. A desktop unit typically has a CPU
(Central Processing Unit), monitor, keyboard and mouse. Introduction of
desktops popularized use of computers among common people as it was compact and
affordable.
Riding
on the wave of desktop’s popularity many software and hardware devices were
developed specially for the home or office user. The foremost design
consideration here was user friendliness.
Laptop
Despite
its huge popularity, desktops gave way to a more compact and portable personal
computer called laptop in 2000s. Laptops are also called notebook
computers or simply notebooks. Laptops run using batteries and
connect to networks using Wi-Fi (Wireless Fidelity) chips. They also have chips
for energy efficiency so that they can conserve power whenever possible and
have a longer life.
Modern
laptops have enough processing power and storage capacity to be used for all
office work, website designing, software development and even audio/video
editing.
Tablet
After
laptops computers were further miniaturized to develop machines that have
processing power of a desktop but are small enough to be held in one’s palm.
Tablets have touch sensitive screen of typically 5 to 10 inches where one
finger is used to touch icons and invoke applications.
Keyboard
is also displayed virtually whenever required and used with touch strokes.
Applications that run on tablets are called apps. They use operating
systems by Microsoft (Windows 8 and later versions) or Google (Android). Apple
computers have developed their own tablet called iPad which uses a
proprietary OS called iOS.
Server
Servers
are computers with high processing speeds that provide one or more services to
other systems on the network. They may or may not have screens attached to
them. A group of computers or digital devices connected together to share
resources is called a network.
Servers
have high processing powers and can handle multiple requests simultaneously.
Most commonly found servers on networks include −
- File or storage
server
- Game server
- Application
server
- Database server
- Mail server
- Print server
Mainframe
Mainframes are computers used by organizations like
banks, airlines and railways to handle millions and trillions of online
transactions per second. Important features of mainframes are −
- Big in size
- Hundreds times
Faster than servers, typically hundred megabytes per second
- Very expensive
- Use proprietary
OS provided by the manufacturers
- In-built
hardware, software and firmware security features
Supercomputer
Supercomputers are the fastest computers on Earth. They are
used for carrying out complex, fast and time intensive calculations for
scientific and engineering applications. Supercomputer speed or performance is
measured in teraflops, i.e. 1012 floating point operations per second.
Chinese
supercomputer Sunway TaihuLight is the world’s fastest supercomputer
with a rating of 93 petaflops per second, i.e. 93 quadrillion floating point
operations per second.
Most
common uses of supercomputers include −
- Molecular
mapping and research
- Weather
forecasting
- Environmental
research
- Oil and gas
exploration
