Description of classification of computers

1. Types of Computer
On the basis of data handling capabilities, there are three types of computer:
1. Analog Computer
2. Digital Computer
3. Hybrid Computer
Analog Computer:-
 It is particularly designed to process analog data.
 Continuous data that changes continuously and cannot have discrete values is called
analogue data.
 Analog computer is used where we don’t need exact values or need approximate
values such as speed, temperature, pressure etc.
 It can directly accept the data from the measuring device without first converting it
into numbers and codes.
 It measures the continuous changes in physical quantity. It gives output as a reading
on a dial or scale. For example speedometer, mercury thermometer, etc.

2. Digital Computer:
 In Digital Computers data are send into discrete form.
Digital computers are designed in such a way that it can easily perform calculations and logical
operations at high speed.
It takes raw data as an input and processes it with programs stored in its memory to produce the
final output.
 It only understands the binary input 0 and 1, so the raw input data is converted to 0 and 1 by the
computer and then it is processed by the computer to produce the result or final output.
All modern computers, like laptops, desktops including smartphones are digital computers.

3. Hybrid Computer:
• As the name suggests hybrid, which means made by combining two different things.
• Similarly, the hybrid computer is a combination of both analog and digital computers.
• Hybrid computers are fast like an analog computer and have memory, and accuracy like a digital
computer.
• So, it has the ability to process both continuous and discrete data.
• For working when it accepts analog signals as input then it converts them into digital form by
sampling and quantization before processing the input data.
• So, it is widely used in specialized applications where both analog and digital data is required to
be processed.
• A processor which is used in petrol pumps that converts the measurements of fuel flow into
quantity and price is an example of a hybrid computer.

4. Categories of computer
On the basis of computing power and speed there are 4 types of computers
 Supercomputer
 Mainframe computer
 Personal Computer
 Embedded Computer

5. Supercomputer
• The fastest, most powerful, and most expensive computer.
• Capable of processing more than one quadrillion instructions in a single second.
• Supercomputers generally run one program at a time, as fast as possible.
• Applications requiring complex, sophisticated mathematical calculations use
supercomputers.
• Large-scale simulations and applications in medicine, aerospace, automotive
design, online banking, weather forecasting, nuclear energy research, and
petroleum exploration.
Mainframe
• A large, expensive, powerful computer that can handle hundreds or thousands of
connected user simultaneously.
• Second largest computers after supercomputers.
• Capable of great processing speeds and data storage.
• With mainframes, enterprises are able to bill millions of customers, prepare
payroll for thousands of employees, and manage thousands of items in inventory.

6. • Mainframe is used in large organizations such as hospitals, universities, large
businesses, banks or insurance companies that need to manage large amount of
centralized data.
Personal computer
A personal computer is a computer that can perform all of its input, processing,
output, and storage activities by itself.
A personal computer contains a processor, memory, and one or more input, output,
and storage devices. Personal computers also often contain a communications
device.
Two types of personal computers are desktop computers and mobile computers.
Mobile Computers and Mobile Devices
 A mobile computer is a personal computer you can carry from place to place.
Similarly, a mobile device is a computing device small enough to hold in your
hand.

7. • Mobile computers
i. Notebook Computers
• A notebook computer, also called a laptop computer, is a portable, personal
computer often designed to fit on your lap. Notebook computers are thin and
lightweight, yet they can be as powerful as the average desktop computer.
ii. A net book
• Smaller, lighter, and often not as powerful as a traditional notebook computer.
Most net books cost less than traditional notebook computers, usually only a few
hundred dollars.
iii. Tablet PCs
• Tablet PC is a special type of notebook computer that allows you to write or draw
on the screen using a digital pen. Tablet PCs are useful especially for taking notes
in lectures, at meetings, conferences, and other forums where the standard
notebook computer is not practical.
• Mobile devices
Some mobile devices are Internet-enabled, meaning they can connect to the
Internet wirelessly.
Five popular types of mobile devices are smart phones, PDAs, handheld
computers, portable media players, and digital cameras.

8. i. Smart Phones
• Internet-enabled phone. Provides personal information management function such as a
calendar, an appointment book, an address book, a calculator, and a notepad.
• Send and receive e-mail messages and access the web.
Include built-in digital cameras
ii. PDA (personal digital assistant)
Provides personal information management functions such as a calendar, an
appointment book, an address book, a calculator, and a notepad.
• Most PDAs also offer a variety of other application software such as word processing,
spreadsheet, personal finance, and games.
iii. Handheld Computers
Small enough to fit in one hand.
Communicate wirelessly with other devices or computers and also include a digital pen
or stylus for input.
Industry-specific and serve the needs of mobile employees, such as meter readers and
parcel delivery people , whose jobs require them to move from place to place.

9. • iv. Portable Media Players
A mobile device can store, organize, and play digital media.
Can listen to music; watch videos, movies, and television shows; and view photos on
the device’s screen.
• v. Digital Cameras
Device that allows users to take pictures and store the photographed images digitally,
instead of on traditional film.
While many digital cameras look like a traditional camera, some are built into smart
phones and other mobile devices.
 Embedded Computers
• Special-purpose computer that functions as a component in a larger product.
Embedded computers are everywhere — at home, in your car, and at work.
Perform various functions, depending on the requirements of the product in which they
reside.