1. COMPUTER FUNDAMENTALS

2. Introduction to Computers
The word “computer” comes from the word “compute", which means, “to calculate”.
Thereby, a computer is a electronics device that can perform arithmetic operations at high speed.
A computer is also called a “data processor” because it can store ,process & retrieve data whenever required.

3. Introduction to Computers
Software - Word, PowerPoint, Excel, etc.
Fun stuff - Games, Photos, etc.
Operating Systems – Microsoft, Unix 3

4. Data Processing 4

5. Characteristics of Computer
Automatic
Speed
Accuracy
No IQ
Diligence 5

6. Basic operation of Comp. System
INPUTTING
STORING
PROCESSING
OUTPUTTING
CONTROLLING 6

7. Basic organization of a computer system7

8. Input Unit 8

9. Output Unit 9

10. Storage Unit 10

11. Types of Storage 11

12. 12

13. Central Processing Unit13

14. Memory Units 2. Contents - info stored
Memory is divided into storage locations called memory cells. Associated with each memory location are: 1. Address - position of a cell in memory
2. Contents - info stored 14

15. Memory Units Everything is manipulated as 0s and 1s
stored using two-state devices:
switches, transistors, vacuum tubes.
On/Off states easily compare to the binary numbering system, Base 2.
On = 1, Off = Binary Digit = Bit

16. Memory Units Bits are grouped into bytes ( 8 bits = 1 byte)
Data stored in 1 byte
Bits are grouped into bytes ( 8 bits = 1 byte)
Each Memory Cell is 1 byte Bytes are grouped into words (length is dependent on the machine)
The computer handles data in multiples
of bit chunks (bytes)

17. Memory Units Also called as Primary Memory unit. 2 most important are:
MAIN MEMORY UNIT:
Also called as Primary Memory unit.
2 most important are:
RAM
ROM
They work in different ways and perform distinct functions. 17

18. RAM (Random Access Memory)18

19. ROM (Read Only Memory) 19

20. Types of ROM 20

21. Types of ROM 21

22. Cache Memory 22

23. Classification of Computers
Computers Generations
“Generation" in computer talk is a step in technology. It provides a framework for the growth of computer industry.
Till today there are five computer generations: 23

24. 24

25. 25

26. 26

27. 27

28. Electronics Devices 28

29. Input Devices Also known as Peripheral devices.
Used to enter data from the outside world into primary storage.
For e.g.:
Keyboard
Mouse
Electronic Pen
Joystick
Scanner ,etc

30. Keyboard

31. Mouse Mouse is a point-and-draw device. Move in all directions.
Electronic Pen
Point-and-draw device
Used to directly pt with it on the screen to select icons or to draw graphics on screen.
Can write with it on a special pad for direct I/P of written information to a system.

32. Joystick
Pointing Device.
Moved forward,backward,left & right.
Button on the top is provided for selection.
USES:
Commonly used for video games,for controlling industrial robots.

33. Scanner
,etc.

37. OCR (Optical Character reader)
Used to recognize alphanumeric characters.
Reflected light converts into binary no.
Dark area absorb the light whereas light is reflected by lighted areas.
Reflected light falls on Photocells which provide binary data corresponding to dark and light areas.
A B C D E………………………….z
…………………………………………...9
‘ { } % ? etc.

38. Monitor
Printer
Speaker
Screen image projector ,etc

39. Monitors are the most popular o/p device used for producing soft-copy of the o/p.
Types of Monitor:
CRT Monitor
LCD Screens

40. CRT Monitors This acronym stands for “Cathode Ray Tube”
Very widespread
Cheap
Good performance

41. CRT Monitors

42. The Shadow Mask

43. Working method of CRT monitor
The back of the tube has a negatively charged cathode, so called electron gun. The electron gun shoots electrons down the tube and onto a positively charged screen. The screen is coated with a pattern of red, green and blue phosphor dots that will glow when struck by the electron stream. The three dots together make up a pixel.

44. LCD Screens
LCD means Liquid Crystal display
Good quality

45. How LCD works?
There is a thin liquid cristal layer between a horizontal and a vertical filter. Thanks to an appropriate voltage liquid cristals get arranged and light can pass the filters. This light will appear on the screen.
In color LCDs each individual pixel is divided into three cells, or subpixels, which are colored red, green, and blue. Each subpixel can be controlled independently to yield thousands or millions of possible colors for each pixel.

46. Printers Dot matrix Inkjet Laser Drum ,etc.
A computer printer is a device that produces a hard copy of documents stored, usually on physical print media such as paper.
Main types of Printers
Dot matrix
Inkjet
Laser
Drum ,etc.

47. Dot Matrix Printer

48. Inkjet Printers

49. Inkjet Printers

50. Inkjet Printers

51. Laser Printers

52. Laser Printers

53. Drum Printers They are Line printer coz it print one line at a time.
Have a solid cylindrical drum with characters embossed on its surface in the form of a circular bands.
Set of hammer mounted in front of the drum in such a manner that an inked ribbon & paper can b placed b/w the hammer & drum.

54. Drum Printers
It can only print a pre-defined set of characters in a pre-defined style that is embossed on the drum.
The drum would have to complete one full revolution to print each line.
Drum printers are impact printers,hence they can b used to produce multiple copies by using carbon paper.

55. Drum Printers

56. Screen Image Projector

59. Magnetic Tape

60. Magnetic Tape

61. Advantages of Magnetic Tape

62. Limitation of Magnetic Tape

63. Magnetic Disk

64. Magnetic Disk

65. Magnetic Disk

66. Magnetic Disk

67. Magnetic Disk Access Time

68. Magnetic Disk

69. Floppy Disk

70. Floppy Disk
Data is recorded on disk in concentric circular bands called tracks
Each track is divided into pie-shaped wedges called sectors.Two or more sectors combine to form a cluster.

71. Floppy Disk
Most computers maintain on the disk a table with the sector and track locations of data. This table, the file allocation table (FAT), enables the computer to locate data easily.

73. Hard Disk

74. Zip/Bernoulli Disk

75. Disk Pack

76. Winchester Disk

77. Optical Disks

78. Optical Disks Storage organization

79. Types of Optical Disks

80. CD-R (WORM)

81. CD-RW

82. DVD

83. Optical Disks CD-ROMs: Compact Disc Read-Only Memory
can store up to 6 Mega Bytes
CD-R: Compact Recordable
holds the same storage, it is recordable once.
CD-RW: Compact Disc Re-Writeable
are read and writable, but does not have the same capacity, because it uses some magnetic technology.
DVDs: Digital Versatile Disc
can hold up to 17 Giga Bytes. Used by the contents industries.

119. OPERATING SYSTEM
A program that acts as an intermediary between a user of a computer and the computer hardware.
Operating system goals:
Execute user programs and make solving user problems easier.
Make the computer system convenient to use.
Use the computer hardware in an efficient manner.

120. OPERATING SYSTEM OS is a resource allocator Manages all resources
Decides between conflicting requests for efficient and fair resource use
OS is a control program
Controls execution of programs to prevent errors and improper use of the computer

121. OPERATING SYSTEM

122. Logical Architecture of a Computer System
This operating system layers hides the details of the hardware from the programmer
Provides the programmer with convenient interface.

123. Parameters for measuring system performance

124. Functions of OS Process Management Memory Management File Management
Security
Command Interpretation

125. Process Management
A process (also called job) is a program in execution.
Process Management manages the processes submitted to a system in a manner to minimize idle time of processors (CPUs,I/O processors,etc.)

126. Process Management mechanism in early computers

127. Multiprogramming

128. Uniprogramming

129. Multiprogramming System

130. Process state in multiprogramming

131. Multitasking
Interleaved execution of multiple jobs (often referred to as task of same user)in a single-user system.
Computer system used for multitasking is uniprocessor systems(having only one CPU)

132. Multiprocessing

133. Multiprocessing System

134. Time-Sharing Simultaneously interactive use of a computer system.
Short period during which a user process gets to use CPU is known as TIME SLICE,TIME SLOT or QUANTUM.
CPU is taken away from a running process when the allotted time slice expires.

135. Process State Diagram of Time-Sharing System

136. Advantages of Time-Sharing
Reduces CPU idle time.
Provides advantages of quick response time.

137. Memory Management
Keeps track of parts of memory in use and parts not in use.
Allocates memory to processes as needed and deallocates when no longer needed.

138. Uniprogramming Memory Model
Used in systems that process one job only at a time.

139. Multiprogramming Memory Model

140. Multiprogramming with fixed no. of memory partition

141. Multiprogramming with variable no. of memory partition

142. Multiprogramming with variable no. of memory partition

143. Virtual Memory

144. Virtual Memory Realization

145. File Management

146. File access Method

147. File Operation

148. File Extensions .c c source program file. .txt general text file.
.doc microsoft world document file.
.xls microsoft excel spreedsheet file.

149. Security Deals with destruction and unauthorized access.
Types of Security:
External Security : Deals with fire,floods etc.
Internal Security : Deals with user authentication, access control, cryptography mechanism.

150. Security

151. Command Interpretation

152. Command Interpretation