A computer is an electronic machine that accepts information
(Data), processes it according to specific instructions, and
provides the results as new information. Monitor Floppy Disk Drive
System Unit Keyboard CD-ROM / DVD-ROM Drive Mouse Slide 2
Chapter:o1 Computer overview => Computer: A computer is an
electronic device that can perform a different types of operations
in accordance with set of instructions is called program. =>
Data: Data are raw facts. =>Information: Information is
meaningful data. Slide 3 Slide 4 => Input-Process-Output(IPO
Cycle) : Certain input is needed to accomplished a task, a process
is carried out on the input to obtain the output. Functional
Components of a computer: In IPO Cycle, First stage is performed in
computer by input unit, Second stage is performed by its central
processing unit and the Third stage is performed by output unit.
The main memory holds the input and intermediate output during the
processing. INPUT UNIT MAIN MEMORY CENTRAL PROCESSING UNIT OUTPUT
Slide 5 => INPUT UNIT: The input unit is performed by the input
devices attached to the computer. Input unit is responsible for
taking input and converting it into computer understandable
form(the binary code). EXAMPLES:KEYBOARD,MOUSE MICR, OMR, OCR,
JOYSTICK. => Central Processing Unit: The CPU is the control
Centre for a computer.it guides, directs, governs, its performance.
It is brain of computer. Slide 6 => The CPU divided into two
parts: (a).Arithmetic Logic UNIT(ALU): The ALU performs all four
arithmetical (+, -,*,/) and some logical operations(, =,). (B)
CONTROL UNIT(CU): The CU control and guides the interpretation,
flow and manipulation of all data and information. The CU sends
control signals until the required operation are done properly by
ALU and memory. It also responsible for execute the program. The CU
gets program instruction from memory and executes the one after the
other. After getting the instructions from memory in CU, the
instruction is decoded and interpreted. Slide 7 =>OUTPUT UNIT:
The output unit is performed by the output devices attached to the
computer. the output coming from CPU is in the form of electrical
binary signals which needs conversion in some form which can be
easily understood by human beings i.e. characters, graphical or
audio visual. Examples: Monitor, printer, plotter, speaker. =>
MEMORY: The memory is a device which can store the data and
information. => MEMORY CELL: It is a device which can store a
symbol selected from set of symbols. bit cell 0 cell 1 010 0 0110
Slide 8 => BYTE OR NIBBLE: A group of 8 bits is called byte and
a group of 4 bits is know as nibble. UnitShort NameFull Name 1
BitBitBinary Digit 8 Bits1 ByteByte 2 10 i.e. 1024 bytes1 KBKilo
Byte 2 10 i.e. 1024 KB1 MBMega Byte 2 10 i.e. 1024 MB1GBGiga Byte 2
10 i.e. 1024 GB1TBTerra Byte 2 10 i.e. 1024 TB1PBPeta Byte 2 10
i.e. 1024 PB1EBExa Byte 2 10 i.e. 1024 EB1ZBZetta Byte 2 10 i.e.
1024 ZB1YBYotta Byte 2 10 i.e. 1024 YB1 BRONTO BYTEBronto Byte 2 10
i.e. 1024 Bronto Bytes 1 GEOP BYTEGeop Byte Slide 9 => There are
two types of memory (a). Primary (Main ) Memory: It is also know as
temporary Memory. Ram and Rom (b). Secondary Memory: To store the
data and information permanently. CD, Hard disk. => Hardware :
The physical and tangible parts of the computer. i.e. The
components that can seen and touched. Monitor,mouse etc. =>
peripherals: The peripherals are devices that surround the system
unit. Examples: keyboard, mouse, speaker, printer, monitor. =>
Software: The set of program that govern the operation of a
computer system. Slide 10 Types of Software There are two types of
software 1.System software 2. Application Software System software:
The software that controls internal computer operations is called
system software system software Divided into two parts Operating
system Language system. Slide 11 Operating system(os): An operating
system is a program which acts as an interface between a user and
the hardware(i.e. all computer resources) Functions of operating
system: (i).It provide the instructions to prepare user
interface.i.e, way to interact with user whether through typed
commands or through graphical symbols. (ii). Loads necessary
programs (into the computer memory) which are required for proper
compute functioning. (iii). Coordinates how programs work with the
CPU, keyboard, Mouse, Printer, and other Hardware as well as with
other software (iv). Manages way information is stored on and
retrieved from disks Slide 12 A set of software instructions that
tells the computer what to do is called a computer program. Major
Component of Computer System are: Slide 13 Slide 14 . Slide 15
Interpreter: IT Converts a High level Language program into machine
language by converting and executing it line by line. if there is
any error in any line, it reports it at the same time and program
execution cannot resume until the error is rectified. Once a given
instruction has been executed, then it translates and executes the
next, and so on. Compiler: It Translate(convert) the Entire HLL
program into machine language program in one go, and reports all
errors of the program along with the line numbers. All instructions
are compiled before any are executed by the CPU. Slide 16
Application Software: It is a set of programs necessary to carry
out operations for a specified application. => Application
software Categories into two types: (a). Customized Application
software : This type of software is tailor made software according
to a users requirements. The software is developed to meet all the
requirements specified by the user. (b). General Application
software : This type of software is developed keeping in mind the
general requirements for carrying out specific task Slide 17
Strength and Weakness of a computer: => Computer Strengths: (i).
Speed: Computer are much faster as compared to human beings. A
computer can perform a task in a minute that may take day if
performed manually. (ii). High storage Capacity: Computers can
store a large amount of information in very small space. (iii).
Accuracy: Computer s can perform all tha calculations and
comparisons accurately provided the hardware does not malfunction.
(iv). Reliability: Computers can immune(protect) to tiredness and
boredom or fatigue(mental exhaustion). (v). Versatility: Computers
can perform repetitive jobs efficiently. They even can work in the
area where human brain can err. Slide 18 Computer Weakness: (i).
Lack of Decision Making Power: Computer cannot decide on their own.
(ii). IQ Zero: Computers are dumb machines with zero IQ =>
FIRMWARE: It is prewritten program that is permanently stored in
read only memory (ROM). It configures the computer and not easily
modifiable by the user. Example: BIOS(BASIC INPUT OUTPUT SERVICE)
=> Liveware: The people associated with and benefited from the
computer system. Slide 19 The origin of computers can be traced
back to inventors who were interested in processing information and
developing devices to simply tedious arithmetic calculations. Slide
20 Abacus(3000BC) allowed the user to manipulate data Babylon, 3000
BC Still in use today beads on rods to count and calculate Slide 21
2- The Roman Numerals IIIIIIIVVVIVIIVIIIIX X 3- The Arabic Numerals
(base 10) 0 123456789 10 Ancient Time Slide 22 Slide Rule 1962
based on Napiers rules for logarithms used until 1970s It
simplified and used logs to transform multiplication problem to
addition problem and division to subtraction Slide 23 The Pascaline
is a mechanical calculating(adding) device invented by the French
philosopher and mathematician Blaise Pascal in 1642. It capable of
addition and subtraction.it worked on clock work mechanism
principle. 1642 Slide 24 The Leibniz Wheel was invented by the
famous mathematician Leibniz in 1671.It perform( +, -, *, / ). this
machine performed multiplication through repeated addition of
number. 1671 Slide 25 =>Punched Cards were used by the French
weaver Joseph Jacquard in 1801. The cards carried weaving
instructions for the looms, later this idea offered a great use for
storing info. 1801 Slide 26 =>In 1822 Charles Babbage (English
mathematician, philosopher), sometimes called the father of
computing built the Difference Engine. =>Machine designed to
automate the computation (tabulation) of polynomial functions
(which are known to be good approximations of many useful
functions) 1852 1822 =>Based on the method of finite difference
=>Implements some storage Slide 27 Difference Engine c.1822 huge
calculator, never finished Analytical Engine 1833 could store
numbers calculating mill used punched metal cards for instructions
powered by steam! accurate to six decimal places As designed, it
would have been programmed using punch-cards and would have
included features such as sequential control, loops, conditionals
and branching. If constructed, it would have been the first
computer as we think of them today. Slide 28 The Tabulating Machine
Herman Hollerith, American inventor, worked at the Census Bureau
& later taught at MIT A machine which used punch cards and did
the mechanical work of tabulating the population Won the Census
Bureau contest and contract; selling 56 of his Tabulating Machines
Organized his own company and continued to produce the machines for
the census Merged with other companies eventually becoming known as
International Business Machines IBM Slide 29 The IBM Automatic
Sequence Controlled Calculator (ASCC) Computer was created by IBM
for Harvard University, which called it the Mark I. First universal
calculator. Slide 30 It used electro magnetic signals It was slow
machine took 3-5 seconds to perform a calculation It was inflexible
It could perform basic arithmetic as well as complex calculations
Slide 31 Modern age of computers is divided into five generations
of computers First Generation (1949-1955) Second Generation
(1956-1965) Third Generation (1966-1975) Fourth Generation
(1976-Present) Fifth Generation (Present and Beyond) Slide 32 The
First Generation of Computers The first computers used vacuum tubes
for circuitry and magnetic drums for memory, and were often
enormous, taking up entire rooms. They were expensive to operate
and in addition to using a great deal of electricity, generated a
lot of heat, which was often the cause of malfunctions. First
generation computers relied on machine language, the lowest- level
programming language understood by computers, to perform
operations, and they could only solve one problem at a time. Input
was based on punched cards and paper tape, and output was displayed
on printouts. The UNIVAC and ENIAC computers are examples of
first-generation computing devices. The UNIVAC was the first
commercial computer delivered to a business client, the U.S. Census
Bureau in 1951. Slide 33 CHARACTERISTICS First generation computers
were based on vacuum tubes. The operating systems of the first
generation computers were very slow. They were very large in size.
Production of the heat was in large amount in first generation
computers. Air conditioning required Machine language was used for
programming. First generation computers were unreliable. They were
difficult to program and use. Frequent hardware failure
Applications: These computers were used for record keeping and
payroll processing Slide 34 ENIAC (Electronic Numerical Integrator
And Calculator) Developed by John Presper Eckert (1919- 1995) and
John W. Mauchley (1907-1980) Developed in 1946 Space requirement 30
X 50 sq. ft. 30 ton weight and 18000 vacuum tubes 70000 registers,
10000 capacitors 6000 switches and 150,000 watts electicity cosr $
400000 Slide 35 When ENIAC completed calculations it inform the
users by turning on a sequence of lights It was used until 1955
Only one system of ENIAC was developed When operated the lights of
near by area were dimmed Slide 36 EDVAC (Electronic Discrete
Variable Automatic Calculator) Developed by John Von Neuman (1903-
1957) It contain a memory to store data and programs as well EDSAC
(Electronic Delay Storage Automatic Calculator) Developed in 1949
by Britishes Prop.M.V.Wilkes. IT uses mercury delay lines for
storage. Slide 37 UNIVAC (UNIVersal Automatic Computer) Developed
by John Presper Eckert, Jr., and John Mauchly Developed in 1951
First commercial computer Could manipulate numeric as well as
textual data Slide 38 Slide 39 SECOND GENERATION TIME PERIOD:
1956s- 1965s TECHNOLOGY USED : Transistors SIZE AND SPEED :Lesser
size and increased speed LANGUAGE USED : Assembly language and
languages like COBOL and FORTRAN COST: Cost decreased OTHER
FEATURES : More efficient and reliable. Though the transistors
still generated a great deal of heat that subjected the computer to
damage, it was a vast improvement over the vacuum tube.
Second-generation computers still relied on punched cards for input
and printouts for output. EXAMPLE: UNIVAC 1108, IBM 1401, CDC 1604
UNIVAC 1108 IBM 1401 TRANSISITORS Slide 40 THIRD GENERATION TIME
PERIOD: late 1966s-1975's TECHNOLOGY USED: Integrated Circuit SIZE
AND SPEED: Size Lesser and speed further increased LANGUAGE USED:
Operating System was developed. COST: Cost decreased further OTHER
FEATURES: Instead of punched cards and printouts, users interacted
with third generation computers through keyboards and monitors and
interfaced with an operating system, which allowed the device to
run many different applications at one time with a central program
that monitored the memory. Computers for the first time became
accessible to a mass audience because they were smaller and cheaper
than their predecessors. EXAMPLE : IBM-360 series, Honeywell Model
316, Honeywell 6000 series, CDC 1700. IBM 360/50 Slide 41 FOURTH
GENERATION TIME PERIOD : 1976s-today TECHNOLOGY USED :
Microprocessor SIZE AND SPEED : Reduced size and tremendous speed
LANGUAGE USED : High Level Languages like PASCAL, COBOL, C, C++,
JAVA COST : Reduced Cost OTHER FEATURES : Microprocessors also
moved out of the realm of desktop computers and into many areas of
life as more and more everyday products began to use
microprocessors. As these small computers became more powerful,
they could be linked together to form networks, which eventually
led to the development of the Internet. Fourth generation computers
also saw the development of GUIs, the mouse and handheld devices.
EXAMPLE : Intel 4004, Apple Macintosh The Macintosh 128K, the first
Macintosh, was the first commercially successful personal computer
to use images, rather than text, to communicate.Macintosh 128K
Intel 4004D microprocessor Slide 42 FIFTH GENERATION TIME PERIOD :
today--beyond TECHNOLOGY USED : Microprocessor SIZE AND SPEED :
Reduced size and tremendous speed LANGUAGE USED : Based on
Artificial intelligence COST : Reduced Cost OTHER FEATURES : Fifth
generation computing devices, based on artificial intelligence, are
still in development, though there are some applications, such as
voice recognition, that are being used today. The goal of
fifth-generation computing is to develop devices that respond to
natural language input and are capable of learning and self-
organization. The use of parallel processing and superconductors is
helping to make artificial intelligence a reality. The goal of
fifth-generation computing is to develop devices that respond to
natural language input and are capable of learning and
self-organization. EXAMPLE : Parallel Inference Machine Note:
Artificial Intelligence is the branch of computer science concerned
with making computers behave like humans.Parallel Inference Machine
Voice Recognition is the field of computer science that deals with
designing computer systems that can recognize spoken words. Slide
43 The current classifications of computers place them into Three
categories: Analog Computer Digital Computer Hybrid Computers
Classification of Computers of On the basis of How It Functions
Slide 44 Digital Computers Analog Computers Classification of
Computers of On the basis of How It Functions Operate on continuous
data, like measuring temp. changes Faster Accuracy of an analog
computer is restricted to the accuracy with which physical
quantities can be sensed and displayed. Specific Purpose computers
Digital computers work on discrete data. digital computer can
process data with greater accuracy We generally use digital
computers for business and scientific data processing. Digital
Computers Slide 45 Hybrid computers are computers that comprise
features of analog computers and digital computers.analog
computersdigitalcomputers The digital component normally serves as
the controller and provides logical operations, while the analog
component normally serves as a solver of differential equations.
logical operationsdifferential equations Hybrid Computers Slide 46
Digital Computer classified into two types (i). Purpose wise (ii).
Size and Performance wise (i). Purpose wise digital computer are
classified into two types. (a). Special-purpose computer: It is
designed to performed a specific task. the instructions to carry
out the task are permanently stored in the machine. (b).
General-purpose computer: it can work on different types of
programs input to it and be used in countless applications. The
program are not permanently stored. Slide 47 The current
classifications of computers place them into five categories:
Embedded computer,,Microcomputers (Personal Computers)
Minicomputers, Mainframes, Super Computers, Size and Speed Based
Classification of digital Computer Systems Slide 48 => Embedded
computers: These computers are typically preprogrammed for a
specific task, such as tuning to a particular television frequency.
Examples: television, washing machine.etc. Slide 49 PERSONAL
COMPUTER The term microcomputer, also known as personal computer
(PC), or a computer that depends on a microprocessor. A
microcomputer contains a central processing unit (CPU) on a
microchip (the microprocessor), a memory system (read-only memory
and random access memory), placed on a motherboard. Example:
desktop, notebook, laptop, handheld devices. Charcteristics:
developed in 1980 designed for single user not very powerful or
expensive found in homes Slide 50 Micro computer also divided into
three types PDA(Personal digital assistants) Laptops and desktop
personal computer. Workstations: Between minicomputer and
microcomputer- in terms of processing power. Looks like PC and used
by one person. Slide 51 MINICOMPUTER Another term rarely used
anymore, minicomputers fall in between microcomputers (PCs) and
mainframes (enterprise servers). Minicomputers are normally
referred to as mid-range servers now. Characteristics: Smaller than
mainframe Can do several jobs at once Can be used by many people at
one time Used by small companies Slide 52 MAINFRAME In the early
days of computing, mainframes were huge computers that could fill
an entire room or even a whole floor. As the size of computers has
decreased while the power has increased, the term mainframe has
fallen out of use in favor of enterprise server. You'll still hear
the term used, particularly in large companies to describe the huge
machines processing millions of transactions every day.
Characteristics: Expensive Powerful and fast Is not limited to one
job Used by business and small government organizations The main
difference between a supercomputer and a mainframe is that a
supercomputer channels all its power into executing a few programs
as fast as possible, whereas a mainframe uses its power to execute
many programs simultaneously. Slide 53 SUPER COMPUTER The fastest
type of computer. Supercomputers are very expensive and are
employed for specialized applications that require immense amounts
of mathematical calculations. For example, weather forecasting
requires a supercomputer. Other uses of supercomputers include
animated graphics,, nuclear energy research, and petroleum
exploration. Characteristics Powerful Expensive Dedicated to one
purpose - weather, satellites, military Used by large governments
or very large companies Can be used by thousands of people at the
same time Very large - fill rooms Slide 54 Sixteen racks of IBM's
Blue Gene/L supercomputer can perform 70.7 trillion calculations
per second, making it the fastest machine known so far. Slide
55
