The document provides a history of computers from early mechanical devices like the abacus and Difference Engine to modern electronic computers like ENIAC, the first general-purpose electronic digital computer. It describes the evolution of computer hardware from vacuum tubes to transistors to integrated circuits. It also covers different types of computers like supercomputers, mainframes, minicomputers, and microcomputers. Finally, it discusses the basic elements of a computer including input devices, output devices, software, and types of software.

1. THE INSTITUTE OF CHARTERED ACCOUNTANTS OF INDIA
HISTORY OF
COMPUTERS
AND
ITS TYPES
AND
ITS ELEMENTS
SUBMITTED BY :-
HEMITA DUA
ROLL NO 26
NR0 0332001
BATCH NO – VN-06-14-B
SUBMITTED TO :-
MR. ALOK GUPTA
MR. MAHESH PRASAD

2. CONTENTS
• EARLY COMPUTERS
• DIFFERENCE ENGINES
• ABACUS
• Mark-1, ENIAC , UNIVAC
• COLOSSUS
• TRANSISTORS AND VACCUM TUBES
• INTEGRATED CIRCUITS
• SMARTCOMPUTERS
• TYPES OF COMPUTER
• SUPERCOMPUTER
• MAINFRAME
• MINICOMPUTER
• WORKSTATIONS
• MICROCOMPUTERS
• OTHERS ( PORTABLE AND EMBEDDED)
• ELEMENTS OF COMPUTER
• INPUT DEVICES (KEYBOARD , MOUSE)
• INPUT DEVICES(SCANNER , WEB CAM)
• INPUT DEVICES(JOYSTICK , BAR CODE READER)
• OUTPUT DEVICES (MONITOR)
• OUTPUT DEVICES (PRINTER)
• PRINTERS
• SOFTWARE
• TYPES OF SOFTWARE

3. EARLY
COMPUTERS
A computer is a general purpose device that can be programmed to carry out a
set of arithmetic or logical operations automatically. The first recorded use of the
word "computer" is also from the 17th century, applied to human computers,
people who performed calculations, often as employment. The first computer
devices were conceived of in the 19th century, and only emerged in their modern
form in the 1940s.
In World War II, mechanical analog computers were used for specialized military
applications. During this time the first electronic digital computers were developed.
Originally they were the size of a large room, consuming as much power as several
hundred modern personal computers(PCs).

4. DIFFERENCE
ENGINES
• Charles Babbage, an English mechanical engineer and polymath, originated the concept
of a programmable computer. Considered the "father of the computer”, he conceptualized
and invented the first mechanical computer in the early 19th century.
• He designed the DIFFERENCE ENGINE in 1822 , which was used to prepare mathematical
tables. It had many similarities with the modern computers.
• A difference engine is an automatic mechanical calculator designed to tabulate polynomial
functions . The name derives from the method of divided differences, a way to interpolate or
tabulate functions by using a small set of polynomial coefficients.

5. ABACUS
• ABACUS is the first device known for doing
calculations. It was invented more than 5000
years ago. It was used in China for counting and
mathematical calculations.
• Today, abaci are often constructed as a bamboo
frame with beads sliding on wires, but originally
they were beans or stones moved in grooves in
sand or on tablets of wood, stone, or metal. The
user of an abacus is called an abacist.

6. EARLY COMPUTERS
• MARK-1 : It was the first automatic digital computer. It was made in
year the year 1944.
• ENIAC (ELECTRONIC NUMERIC INTEGRATOR AND CALCULATOR) : It was
the first electronic general-purpose computer. When ENIAC was
announced in 1946 it was heralded in the press as a "Giant Brain". It had a
speed of one thousand times that of electro-mechanical machines. This
computational power, coupled with general-purpose programmability,
excited scientists and industrialists.
• UNIVAC -1:UNIVAC is an acronym for UNIVersal Automatic Computer.
It is the first general purpose computer for commercial use. It was made in
1951.

7. COLOSSUS
• Colossus was the first electronic digital programmable computing device,
and was used to break German ciphers during World War II. It used a large
number of valves (vacuum tubes). It had paper-tape input and was
capable of being configured to perform a variety of boolean
logical operations on its data, but it was not Turing complete. Colossus
Mark I contained 1500 thermionic valves (tubes), but Mark II with 2400
valves, was both 5 times faster and simpler to operate than Mark 1,
greatly speeding the decoding process.

8. Transistors replace vacuum tubes in
computers
• The bipolar transistor was invented in 1947. From 1955 onwards
transistors replaced vacuum tubes in computer designs, giving rise to the
"second generation" of computers. Compared to vacuum tubes,
transistors have many advantages: they are smaller, and require less
power than vacuum tubes, so give off less heat. Silicon junction transistors
were much more reliable than vacuum tubes and had longer, indefinite,
service life. Transistorized computers could contain tens of thousands of
binary logic circuits in a relatively compact space.

9. Integrated circuits replace transistors
• The next great advance in computing power came with the advent of
the integrated circuit. The idea of the integrated circuit was first conceived
by a radar scientist working for the Royal Radar Establishment of the
Ministry of Defence , Geoffrey W.A. Dummer . Dummer presented the first
public description of an integrated circuit at the Symposium on Progress in
Quality Electronic Components in Washington, D.C. on 7 May 1952. This
new development heralded an explosion in the commercial and personal
use of computers and led to the invention of the microprocessor.

10. Mobility and the growth of Smartphone
computers
• With the continued miniaturization of computing resources, and
advancements in portable battery life, portable computers grew in
popularity in the 1990s.The same developments that spurred the
growth of laptop computers and other portable computers allowed
manufacturers to integrate computing resources into cellular
phones. These so-called Smartphones run on a variety of operating
systems and are rapidly becoming the dominant computing device
on the market, with manufacturers reporting having shipped an
estimated 237 million devices in 2Q 2013.

11. TYPES OF COMPUTER
SUPERCOMPUTERS
MAINFRAMES
MINICOMPUTERS
WORKSTATIONS
MICROCOMPUTER

12. SUPERCOMPUTER
 Largest, fastest, most powerful, and most expensive
computers made
 Used primarily for scientific applications that are
mathematically intensive
 Used in weather forecasting and seismic analysis
 Speed of modern supercomputers is measured in
nanoseconds and gigaflops
 Can perform at up to 128 gigaflops, and use bus widths of 32
or 64 bits
 The massively parallel processors of today contain hundreds
of processors

13. MAINFRAMES
 Suitable for input/output intensive operations
 Generally having multiprocessing capabilities
 Speed is measured in megaflops
 Generally limited to eight or fewer processors
 Host processor is responsible for controlling the other
processors, all the peripheral devices, and controlling the
other processors
 Front end processors is responsible for handling
communications to and from all the remote terminals
connected to the system
 Back end processor handles data retrieval operations

14. MINICOMPUTERS
 Minicomputers are a little slower
Can perform the same task as mainframes
Slightly less storage and printers are slightly
slower
Referred to as mid range computers

15. WORKSTATIONS
 Powerful desktop computer designed to meet the computing
needs of engineers, architects, and other professionals who
need detailed graphics displays
 Used for COMPUTER-AIDED DESIGN (CAD)
 Also called as SUPERMICRO
 Use Reduced Instruction Set Computer (RISC)
 The DEC ALPHA CHIP was the first microprocessor designed to
work with a 64-bit bus

16. MICROCOMPUTERS
 The new Pentium Pro microcomputers have multiprocessing
capabilities
 Enables multi tasking – a single user variation on
multiprogramming
 The term microcomputer originated in the late 1970s
 people usually mean PC when they use the term
microcomputer

17. OTHERS
• PORTABLE COMPUTERS
1. DOCKING STATIONS
2. PALMTOPS
3. DIGITAL
ASSISTANTS(PDAs)
4. SMART CARDS
• EMBEDDED COMPUTERS
1. Built into special purpose
devices, such as video
game players, microwave
ovens, ‘smart’ alarm
clocks.
2. Also embedded in
automobiles, CD players,
ovens etc.

18. ELEMENTS OF COMPUTER
• HARDWARE
Computer hardware is the collection of
physical elements that constitutes
a computer system. Computer
hardware refers to the physical
parts or components of a computer
such as the monitor
,mouse, keyboard, computer data
storage, hard drive disk (HDD),
system unit (graphic cards, sound
cards, memory, motherboard and
chips), etc. all of which are physical
objects that can be touched.
• SOFTWARE
Software is instructions that can be
stored and run by hardware.Software
is any set of machine-readable
instructions that directs a computer's
processor to perform specific
operations.
Eg., Paint , Open office, Microsoft
Windows
Linux ,Unix ,
Mac OSX,
DOS ,
BIOS Software ,
HD Sector Boot Software,
Device Driver Software i.e Graphics
Driver etc ,
Linker Software ,
Assembler and Compiler Software.

19. INPUT DEVICES
• KEYBOARD
o Consists of a set of typewriter like
keys that enables to enter data
into a computer
o Alphanumeric keys, punctuation
keys, special keys can be seen
o Standard layout is QWERTY
• MOUSE
o It controls the movement of the
cursor or pointer on a display
screen
o Invented by Douglas Engelbart of
Stanford Research Centre in 1963
o PIONEERDE BY XEROX IN THE
1970s
o Types : Mechanical , Opto-mechanical,
Optical

20. INPUT DEVICES
• SCANNER
o Reads text or illustrations printed
on paper and translate the
information into a form that
computer can use
o OCR system translates the image
into ASCII characters
o Uses CCD technology
• WEB CAM
o A webcam is a video camera that
feeds or streams its image in real
time to or through
a computer to computer network.
When "captured" by the
computer, the video stream may
be saved, viewed or sent on to
other networks via systems such
as the internet, and email as an
attachment.

21. INPUT DEVICES
• JOYSTICK
 The pointer moves in the
direction the joystick is pointing
 Includes two buttons called
triggers
 Used for computer gaming ,
CAD/ CAM system
• BAR CODE READER
 Used in supermarkets,
bookshops, etc.
 These are photoelectric scanners
that read the bar codes, or
vertical zebra striped marks
 Uses the UNIVERSAL PRODUCT
CODE (UPC)

22. OUTPUT DEVICES
• MONITOR
 A monitor or a display is an electronic visual display for
computers. The display device in modern monitors is typically
a thin film transistor liquid crystal display(TFT-LCD) thin panel
 CLASSIFICATION
BASED ON COLOUR
• MONOCHROME, GRAY-SCALE,COLOR MONITOR
BASED ON SIGNALS
• DIGITAL, ANALOG MONITOR

23. OUTPUT DEVICE
• PRINTER
 In computing, a printer is a peripheral which makes a persistent human-readable
representation of graphics or text on paper or similar physical
media.
 The world's first computer printer was a 19th-century mechanically driven
apparatus invented by Charles Babbage for his difference engine.

25. SOFTWARE
 SOFTWARE is the non-tangible component of computers.
 Computer software includes all computer programs regardless of their
architecture; for example, executable files , libraries and scripts are
computer software. Yet, it shares their mutual properties:
 Software consists of clearly defined instructions that upon execution,
instructs hardware to perform the tasks for which it is designed.
 Software is stored in computer memory and cannot be touched, just as a
3D model shown in an illustration cannot be touched.
 EXAMPLES : Microsoft Windows, Linux ,Unix ,Mac OSX ,DOS Opera (Web
Browser) ,
Microsoft Word (Word Processing) ,Microsoft Excel (Spreadsheet
software), MySQL (Database Software) ,Microsoft Powerpoint
(Presentation Software) .

26. A diagram showing how the operating
system software and application
software are layered on a
typical desktop computer. The arrows
indicate information flow.
TYPES OF SOFTWARE
Application software uses the
computer system to perform useful
work or provide entertainment
functions beyond the basic
operation of the computer itself.
System software is designed to
operate the computer hardware, to
provide basic functionality, and to
provide a platform for running
application software.