computer history, generations, types and io

39
FUNDAMENTALS of COMPUTER SCIENCE Hem Sagar Pokhrel Lecturer, Prime College

Upload: hem-pokhrel

Post on 15-Jan-2017

194 views

Category:

Technology


4 download

TRANSCRIPT

Page 1: Computer History, Generations, Types and IO

FUNDAMENTALS of

COMPUTER SCIENCE

Hem Sagar Pokhrel

Lecturer, Prime College

Page 2: Computer History, Generations, Types and IO

When Computer Came into existence ?

Page 3: Computer History, Generations, Types and IO

• It was a mechanical adding-machine.

• Invented by 19 year old French mathematician Blaise

Pascal.

• It could only perform addition and subtraction.

• It had 8 wheels and each wheel had 10 digits from 0 to

9.

Pascaline

(1642)

• Improved and strong computing machine which could

multiply, divide and workout square roots apart from

addition and subtraction.

• Invented by German mathematician Gothfried von

Leibnitsz.

• The machine also had handle and gear.

Stepped

Recknor

(1671)

Page 4: Computer History, Generations, Types and IO

3

Charles Babbage 1791-1871

English mathematician, engineer, philosopher and inventor.Originated the concept of the programmable computer, and designed one.Could also be a Jerk.

Page 5: Computer History, Generations, Types and IO

Difference Engine

Numerical tables were constructed by hand using large numbers of human “computers” (one who computes).

Annoyed by the many human errors this produced, Charles Babbage designed a “difference engine” that could calculate values of polynomial functions.

It was never completed, although much work was done and money spent.

Book Recommendation: The Difference Engine: Charles Babbage and the Quest to Build the First Computer

by Doron Swade

Page 6: Computer History, Generations, Types and IO

Analytical Engine

Charles Babbage first described a general purpose analytical engine in 1837, but worked on the design until his death in 1871. It was never built.

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.

Page 7: Computer History, Generations, Types and IO

Augusta Ada Byron King, Countess of Lovelace 1815-1852

Created a program for the (theoretical) Babbage analytical engine which would have calculated Bernoulli numbers.

Widely recognized as the first programmer.

Page 8: Computer History, Generations, Types and IO

Konrad Zuse – Z1 Computer

First freely programmable computer, electro-mechanical punch tape control.

Page 9: Computer History, Generations, Types and IO

• It is believed that the first programmable computer z1was invented in 1936 in Berlin Germany by Konrad Zuse.

• It was programmable machine that was able to remember numbers.

• Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful and more efficient and reliable devices.

First Programmable Computer – Z1

Page 10: Computer History, Generations, Types and IO

• Uses Vacuum tubes as the basic components and magnetic drums and punch cards

as memory.

• Very expensive, use lot of electricity, generated a lot of heat and taking up entire

rooms.

• Vacuum tubes required constant maintenance. This maintenance was very expensive

and could be afforded only by very large organizations.

• This generation computers works on machine language which the lowest- level

programming language.

• They used batch processing operating systems and perform single instruction at a

time.

• Inputs for these computers were based on punched cards and paper taps and output

was displayed on printouts.

• Examples: MARK I, ENIAC, EDVAC, EDSAC, UNIVAC, IBM 650 etc• UNIVAC was the first commercial computer delivered to a business client “the U.S.

Census Bureau” in 1951.

FIRST GENERATION (1942-1959)

Page 11: Computer History, Generations, Types and IO

• Transistors replaced vacuum tubes as CPU component in the second generation of

computers.

• Ferrite cores & magnetic disks were used for memory.

• The transistor was invented in 1947 but used in computer in late 1950s. Transistors

were smaller, faster, cheaper, energy-efficient and more reliable. Thus second

generation computers were smaller, use less power, cheaper and produced less heat.

• Magnetic disk storage increased capacity of storage and magnetic cores for main

storage increased processing speed.

• Symbolic machine language or assembly language was used instead of machine

language, which allowed programmers to make a improved software.

• High level programming languages were also being developed like FORTRAN,

COBOL.

• They used batch processing and multiprogramming operating systems.

• Example: IBM 1400 and 7000 Series, Control Data 3600 etc.

SECOND GENERATION (1959-1965)

Page 12: Computer History, Generations, Types and IO

• Integrated Circuit (IC’s) instead of transistors used in this generation’s computers.

• IC is a silicon chips which reduces the size of computer and increase speed and

efficiency of processing. Each IC is solid state microcircuits which works similar

likes many resistors, transistors, diodes and conductors.

• Now user interacted with third generation computers through keyboard, monitors

and operating system instead of punched cards and printouts.

• In this generation, Remote processing, Time-sharing, Real-time, Multi-

programming Operating System were used.

• High-level language (FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC,

ALGOL-68, etc.) were used during this generation.

• Examples: IBM-360, ICL-1900, IBM-370, and VAX-750.

THIRD GENERATION(1965-1975)

Page 13: Computer History, Generations, Types and IO

• Very large scale Integrated (VLSI) circuits were used in Computer of this

generation. (VLSI circuits are having thousands of transistors in a single chip. )

• Computers of this generation are more powerful, reliable, affordable and compact.

• The Intel 4004 chip, developed in 1971 which is mostly used as Central Processing

unit in theses computers.

• Computers of this generation also saw the development of GUIs, the mouse and

handheld devices.

• In this generation, Time sharing, Real time, Networks, Distributed Operating

System were used in computers.

• All the higher level languages like C and C++, DBASE, etc were used in this

generation.

• Example: IBM PC, Apple-Macintosh etc.

FOURTH GENERATION(1975-1988)

Page 14: Computer History, Generations, Types and IO

• The VLSI technology became ULSI (Ultra Large Scale Integration) technology.

• Millions of transistors are placed in a single IC in ULSI chips.

• Computers of this generation use parallel processing hardware and AI (Artificial

Intelligence) software.

• Higher level languages like C and C++, Java, .Net, etc., are used in this generation.

• 64 bit microprocessors have been developed during this period.

• They are under development and are future of modern computing.

FIFTH GENERATION(1988-till date)

Page 15: Computer History, Generations, Types and IO
Page 16: Computer History, Generations, Types and IO

Differents Types of Computers

Page 17: Computer History, Generations, Types and IO

Before Digital Era..

On the

basis of work.

On the

basis of size.

IBM IBM Compatible Apple/Macintosh On the basis of Brand.

XT AT PS/2

On the basis of Model.

Specific General

On the basis of Purpose.

Page 18: Computer History, Generations, Types and IO

• Most powerful computer system currently available.

They needs a large room to install.

• Minimum world length is 64 bit in super computer. CPU

speed of super computer is minimum 100 MIPS. It is

equivalent to more than 5000 personal computers.

• They uses multiprocessing and parallel processing and is able to handle huge

amount of data.

• Very expensive and are in use for particular applications that require huge

amounts of mathematical calculations.

• Supercomputers are used for Defense systems, weather forecasting, scientific

simulations, animated graphics, fluid dynamic calculations, nuclear energy

research, electronic design, and analysis of geological data.

• Examples: CRAY Research :- CRAY-1 & CRAY-2, PARAM(India), Fujitsu

(VP2000), Hitachi (S820), NEC (SX20), PARAM 10000 by C-DAC, Anupam by

BARC and PACE Series by DRDO.

Super Computer

Page 19: Computer History, Generations, Types and IO

• Able to process large amount of data at very high speed.

• These computers Supports multi-user facility.

• Have many Number of processors varies from one to six.

• They are more powerful than supercomputers because

they support more simultaneous programs. But supercomputers can execute a

single program faster than a mainframe.

• Mainframes computers are used in the Banks, Credit Card Processing,

Insurance Companies, Hospitals, Railways and Airways systems etc. which

need online processing of large number of transactions and requires massive data

storage and processing capabilities.

• Some examples of mainframe computers are IBM 3000 series, Burroughs

B7900, Univac 1180, ICL 39 and CDC 6600.

Mainframe Computer

Page 20: Computer History, Generations, Types and IO

• It is a midsize computer, larger and more powerful

• than most of microcomputers but are smaller and less powerful than

mainframes.

• In general, a minicomputer is a multiprocessing

system capable of supporting from up to 200 users

simultaneously.

• These computers are used when the volume of processing is large for e.g. Data

processing for a medium sized organization.

• Mostly these computers used to control and monitor production processes, to

analyze results of experiments in laboratories, as servers in LANs (Local Area

Networks).

• Examples: PDP 11/45 and VAX 11 etc.

Mini Computer

Page 21: Computer History, Generations, Types and IO

• A microcomputer or Personal Computer uses a microprocessor as its central

Processing Unit.

• Microcomputers are tiny computers that can vary in

size from a single chip to the size of a desktop model.

• They are designed to be used by only one person at a time.

• They have Small to medium data storage capacities 40GB – 2TB.

• Mostly microcomputers are used in the field of desktop publishing, accounting,

statistical analysis, graphic designing, investment analysis, project management,

teaching, entertainment etc.

• First Personal Computer “Apple -1” was designed.

• The common examples of microcomputers are chips used in washing machines,

TVs, Cars and Note book/Personal computers.

• Some examples of microcomputers are IBM PC, PS/2 and Apple Macintosh.

Microcomputer / PC

Page 23: Computer History, Generations, Types and IO

Input and Input Devices

• Input is any data or instructions that are used by a computer.

• An input device is any hardware component that allows you to enter data and

instructions onto a computer.

• In other word, input devices are hardware used to translate words, sounds,

images, and actions that people understand into a form that the system unit can

process.

• Some commonly used input devices are:

1. Keyboard

2. Mouse

3. Joy Stick

4. Light pen

5. Track Ball

6. Scanner

7. Graphic Tablet

8. Microphone

9. Magnetic Ink Card Reader(MICR)

10. Optical Character Reader(OCR)

11. Bar Code Reader

12. Optical Mark Reader(OMR)

Page 24: Computer History, Generations, Types and IO

Keyboard• Keyboard is the most common and very popular input

device which helps in inputting data to the computer.

• The layout of the keyboard is like that of traditional typewriter, although there are

some additional keys provided for performing additional functions.

• When key is pressed, electrical signal is generated which determine which key

was pressed. At the time of key press, raw data is hold by buffer memory of

keyboard.

• Keyboards generally come in two sizes: 84 keys or 101/102 keys, but now

keyboards with 104 keys or 108 keys are also available for Windows and Internet.

• Types of standard Keyboards:

1. XT (Extended Technology): with 83 keys.

2. AT (Advanced technology): with 101 keys.

3. Enhanced technology: with 104 keys.

Page 25: Computer History, Generations, Types and IO

The keys on the keyboard are as follows:

1 Typing Keys: These keys include the letter keys (A-Z) and digit keys

(0-9) which generally give same layout as that of typewriters.

2 Numeric Keypad: It is used to enter numeric data or cursor movement. Generally,

it consists of a set of 17 keys that are laid out in the same configuration used by most

adding machines and calculators.

3 Function Keys: The twelve function keys are present on the keyboard which are

arranged in a row at the top of the keyboard. Each function key has unique meaning

and is used for some specific purpose.

4 Control keys: These keys provide cursor and screen control. It includes four

directional arrow keys. Control keys also include Home, End, Insert, Delete, Page

Up, Page Down, Control(Ctrl), Alternate(Alt), Escape(Esc).

5 Special Purpose Keys: Keyboard also contains some special purpose keys such

as Enter, Shift, Caps Lock, Num Lock, Space bar, Tab, and Print Screen.

Keyboard contd..

Page 26: Computer History, Generations, Types and IO

Mouse• Invented by Douglas Engelbart in 1968 at Stanford Research Institute.

• Mouse is most popular pointing device.

• It is generally a small palm size box with a round ball at its base which senses the

movement of mouse and sends corresponding signals to CPU when the mouse

buttons are pressed.

• Generally it has two buttons called left and right button and a wheel is present

between the buttons.

• Mouse can be used to control the position of cursor on screen, but it cannot be

used to enter text into the computer.

Advantages

• Easy to use

• Not very expensive

• Moves the cursor faster than the arrow keys of keyboard.

Page 27: Computer History, Generations, Types and IO

Bar Code Readers

• Input device used for reading bar coded data (data in form of light and dark

lines).

• Bar coded data is generally used in labelling goods, numbering the books etc.

• It may be a hand held scanner or may be embedded in a stationary scanner.

• Bar Code Reader scans a bar code image, converts it into an alphanumeric

value which is then fed to the computer to which bar code reader is

connected.

Page 28: Computer History, Generations, Types and IO

Touch Screen• Screen with touch sensitive points or program icons.

• When specific point or icon is touched by fingertips,

related programs or prompts are activated.

• Mainly three types:

1. Capacitive

2. Infrared

3. Pressure Sensitive.

Page 29: Computer History, Generations, Types and IO

Scanner• Input device which works more like a photocopy machine.

• It is used when some information is available on a paper and it is to be transferred to

the hard disc of the computer for further manipulation.

• Scanner captures images from the source which are then converted into the digital

form that can be stored on the disc.

• These images can be edited before they are printed.

Microphone• Input device to input sound that is then stored in digital form.

• The microphone is used for various applications like adding sound to a

multimedia presentation or for mixing music.

Page 30: Computer History, Generations, Types and IO

Output and Output Devices

• Output is processed data or information, and typically takes the form of text,

graphics, photos, audio, and/or video.

• Output devices are any hardware used to provide or to create output.

• An output device is any hardware component that conveys information to one or

more people.

• They translate information that has been processed by the system unit into a

form that humans can understand.

• Following are few of the important output devices which are used in a computer:

1. Monitors

2. Printer

3. Graphic Plotter

Page 31: Computer History, Generations, Types and IO

Monitors• Monitors, commonly called as Visual Display Unit (VDU),

are the main output device of a computer.

• It forms images from tiny dots, called pixels that are arranged in a rectangular

form.

• The sharpness of the image depends upon the number of pixels.

• The clarity of a monitor refers to the quality of the displayed images.

• Two main types of monitors are:

1. Cathode-Ray Tubes (CRT): similar to televisions.

2. Flat-panel monitors: much thinner such as Liquid Crystal Display (LCD).

Page 32: Computer History, Generations, Types and IO

• Screen size – The diagonal measurement of the screen surface in inches (15, 17,

19, 21).

• Resolution – The sharpness of the image determined by the number of horizontal

and vertical dots (pixels) that the screen can display (800 x 600, 1024 x 768, 1600

x 1200)

• Refresh rate – The speed at which the screen is redrawn (refreshed) and measured

in Hertz (Hz) (60Hz, 75Hz)

Monitor Specifications

Page 33: Computer History, Generations, Types and IO

1. Cathode-Ray Tube (CRT) Monitor

• The CRT display is made up of small picture

elements called pixels.

• The smaller the pixels, the better the image clarity, or resolution.

• It takes more than one illuminated pixel to form whole character, such as the letter

‘e’ in the word help.

• A finite number of characters can be displayed on a screen

at once. The screen can be divided into a series of

character boxes - fixed location on the screen where a

standard character can be placed.

• Most screens are capable of displaying 80 characters of data

horizontally and 25 lines vertically.

• There are some disadvantages of CRT: Large in Size High power consumption

Page 34: Computer History, Generations, Types and IO

2. Flat-Panel Display Monitor

• Refers to a class of video devices that have reduced

volume, weight and power requirement in comparison

to the CRT.

• You can hang them on walls or wear them on your wrists.

• Current uses of flat-panel displays include calculators, video games, monitors,

laptop computer, graphics display.

• The flat-panel display is divided into two categories:

Emissive Displays - The emissive displays are devices that convert electrical

energy into light. Example are plasma panel and LED(Light-Emitting Diodes).

Non-Emissive Displays - The Non-emissive displays use optical effects to

convert sunlight or light from some other source into graphics patterns.

Example is LCD(Liquid-Crystal Device)

Page 35: Computer History, Generations, Types and IO

Printer

• A printer is a peripheral output device that produces a

physical copy or hard copy of the computer’s output.

• Output device that present the information on paper.

• Two main features of printers are:

1. Resolution - the clarity of images produced and measured in dpi (dots

per inch). The higher the dpi, the better the quality of images produced.

2. Speed – measured in the number of pages printed per minute (ppm).

• Mainly of two types:

1. Impact Printers.

2. Non-impact Printers.

Page 36: Computer History, Generations, Types and IO

Impact Printer Non-Impact Printer

• Head strikes ink coated ribbon to print

information.

• Noisy, slow, and poor quality output.

• Examples: Dot Matrix, Daisy Wheel,

Golf ball etc.

• Thermal, Chemical or Optical

techniques are applied to print

information.

• Noiseless, fast and high quality output.

• Examples: Thermal, Laser, and Inkjet

Printers.

Page 37: Computer History, Generations, Types and IO

Inkjet Printer Laser Printer

• Inkjet printer, also called a bubble-jet,

makes characters by inserting dots of ink

onto paper.

• Letter - quality printouts.

• Cost of printer is inexpensive but ink is

costly

• Laser printer works like a copier

• Quality determined by dots per inch

(dpi) produced.

• Color printers available.

• Expensive initial costs but cheaper

to operate per page

Page 38: Computer History, Generations, Types and IO

Plotter

• A plotter is a printer that uses a pen that moves over a large

revolving sheet of paper.

• It is used in engineering, drafting, map making, and seismology.

• Four types: Drum Plotter, Microgrip Plotters, Flat-bed Plotters,

and Ink-jet Plotters.

Dot Matrix Printers

• Head contains matrix of pins and no. of pins denotes output quality.

• Produce characters and illustrations by striking these pins against an ink ribbon to

produce desired shape.

• Compared to laser and inkjet printers, dot matrix printers are noisy.

Page 39: Computer History, Generations, Types and IO

THANK YOU ! Stay Connected:Facebook: http://www.facebook.com/geeksagar Instagram: http://www.instagram.com/geeksagarTwitter: http://www.twitter.com/NepalisagarLinkedIn: http://www.np.linkedin.com/in/geeksagar