The document discusses different types of personal computers. It describes the four generations of computers from the first generation in the 1940s-1950s which used vacuum tubes and were large, to the current fourth generation starting in 1971 which uses microprocessors on a single chip. It also discusses different models of computers including tower, hand-held, desktop, notebook, laptop, netbook, and tablet PC models. For each type or generation it provides brief details about important features and innovations.

1. DIFFERENT TYPES OF PERSONAL
COMPUTERS
Presented By:
T. Dhana Lakshmi
Branch : CSE

2. Definition of a computer:
A computer is a general-purpose device that can
be programmed to carry out a set
of arithmetic or logical operations automatically. Since
a sequence of operations can be readily changed, the
computer can solve more than one kind of problem.

3. HISTORY OF COMPUTER:
In 1837 Charles Babbage first described his Analytical
Engine which is accepted as the first design for a modern
computer. The analytical engine had expandable memory. The
analytical engine would have had a memory capacity of less
than 1 kilobyte of memory and a clock speed of less than 10
Hertz
In 1937 J.V. Atanasoff, a professor of physics and mathematics at
Iowa State University, attempts to build the first computer without
gears, cams, belts or shafts.
In 1976 Steve Jobs and Steve Wozniak start Apple Computers on
April 1ST and roll out the Apple I, the first computer with a single-
circuit board.

4. Types Of Computers:
Computers can be broadly classified by their speed and computing
power. There are 4generations of computers they are:
 1st generation computers
 2nd generation computers
 3rd generation computers
 4th generation computers

5. First Generation Computers (1940s – 1950s):
First electronic computers used vacuum tubes, and they were huge
and complex. The first general purpose electronic computer was the
ENIAC (Electronic Numerical Integrator And Computer). It was digital,
although it didn’t operate with binary code, and was reprogrammable
to solve a complete range of computing problems. It took up 167
square meters, weighed 27 tons, and consuming 150 kilowatts of
power. It used thousands of vacuum tubes, crystal diodes, relays,
resistors, and capacitors.

6. Second Generation Computers (1955 – 1960):
The second generation of computers came about thanks to the invention of the
transistor, which then started replacing vacuum tubes in computer design.
Transistor computers consumed less power, less heat, and were much smaller
compared to the first generation
The first transistor computer was created at the University of Manchester in
1953. The most popular of transistor computers was IBM 1401.

7. Third Generation Computers (1960s):
The invention of the integrated circuits (ICs), also known as microchips. which
is a semiconductor, allowed them to be much smaller and more practical to
produce. This also started the ongoing process of integrating an ever larger
number of transistors onto a single microchip. During the sixties microchips
started making their way into computers, but the process was gradual, and
second generation of computers still held on.

8. Fourth Generation Computers (1971 – present):
First microchips-based central processing units consisted of multiple microchips for
different CPU components. The drive for ever greater integration and miniaturization
led towards single-chip CPUs, where all of the necessary CPU components were put
onto a single microchip, called a microprocessor. The first single-chip CPU, or a
microprocessor, was Intel 4004.

9. Different models of computer:
1. Tower model
2. Hand-Held model
3.Desktop model
4.Notebook model
5. Laptop model
6. Netbook model
7. Tablet pc model

10. Tower Model:
The term refers to a computer in which the power supply, motherboard, and mass
storage devices are stacked on top of each other in a cabinet. This is in contrast to
desktop models, in which these components are housed in a more compact box. The
main advantage of tower models is that there are fewer space constraints, which
makes installation of additional storage devices easier.

11. A portable computer that is small enough to be held in one’s hand. Although
extremely convenient to carry, handheld computers have not replaced notebook
computers because of their small keyboards and screens. The most popular hand-held
computers are those that are specifically designed to provide PIM (personal
information manager) functions, such as a calendar and address book.
Hand-held computer:

12. A computer designed to fit comfortably on top of a desk, typically with
the monitor sitting on top of the computer. Desktop model computers
are broad and low Desktop models designed to be very small are
sometimes referred to as slim line models.
Desktop model:

13. Notebooks:
Notebooks computers are very light in weight as compare to laptop computers. Its
weight is less than six pounds and placed it easily in briefcase. The basic difference
between the personal computer and notebooks is display screen. In notebook
computers use flat panel technologies to produce non-bulky display screen.

14. Laptop’s:
A laptop computer is a type of personal computers. In laptop computers,
including a keyboard, touchpad, display screen and speakers compiled into
a single unit. It is powered by electricity via an AC adapter. The first
computer described as laptop released in 1983 by Manuel Fernandez.

15. Netbooks:
It is an informal classification of personal computers. But when tablet PCs are coming in
market netbooks are less common. Netbooks have ranged size of 5 inch screen diagonal and
its weight is approx. one kg or 2 to 3 pounds. The netbooks trend came from Toshiba who
launched the Libretto 6 inch netbook whose weight is 840g.

16. Tablet PC:
It is a mobile computer which is larger than PDA or a mobile phone.
Tablet computer integrated with touch screen rather than using physical
keyboard and also using digital pen. In tablet PC you can get a lot of
functions like cell phone functions, wireless internet, GPS navigation and
a video camera. Its weight is varies from 1 to 1.5 kg. Its battery life is
three to ten hours.

17. Computer Peripherals:
The device which is connected to a host computer, but not part of it is
called peripheral device. These are also called input or output devices.
Input, Output & Storage are main types of computer peripherals. A device
such as Headphones, Joysticks, Keyboards, Monitors, Mouse, Speakers,
USB Gadgets, USB Hubs, Webcams are known as Peripherals Devices

18. Advantages of pc’s:
 It may be the storage of your important data and files.
 It may be your handy book.
 It may help you solve problems faster than an ordinary human
being can do.
 It has speed, storage, reliability, consistency and
communications.
 It helps you to find useful information using the Internet.
 It helps in businesses, factories, offices, schools and homes.
 helps you automate various tasks that you can not do
manually
 It helps you organize your data and information in a better
way.
 It has much more computing and calculating power then an
ordinary human.
 It may help your work to be a lot easier

19. Disadvantage’s of pc’s:
 It destroys your social life and interactions with humans if you do not
maintain the balance.
 It may effect to the destruction of your eye sight due to radiation.
 It may cause pimples and wrinkles.
 It may damage your studies and life.
 Too much time in front of monitor may adverse effect your eye sight and can
also make you fat.
 The way it distracts and can deviate our thoughts and activities towards
unproductive activities.
 It could cause violation of privacy, impact on labor force, health risks, impact
on environment, distraction from work, and possible antisocial influences.
 getting away from their real life and getting into bad lines