5. OPERATING SYSTEM
• It is a collection of programs that controls
and manages the computer
• Examples
Windows, Unix, MSDOS
6. Functions Of OS
• It provide an interface between the hardware
and the user.
• It controls and co-ordinate the entire computer
system.
• It controls the allocation and use of various
resource by various user and task.
• It controls the various application programs.
• Scheduling the jobs.
• Process management, Memory management,
Device management etc,.
7. TYPES OF OS
• Single user/ single tasking OS
• Single user/ multi tasking OS
• Multi user/ multi tasking OS
• Time sharing OS
• Virtual storage OS
• Real time system
8. Single user/Single tasking OS
• One user works on the system
• Performs one task at a time
• Take up little space on disk
• Run on inexpensive computers
• Example MS-DOS
9. Single user/Multitasking OS
• User performs many tasks at once
• Most common form of OS
• Require expensive computers
• Tend to be complex
• Example: Windows XP
10. Multi user/Multitasking OS
• Many users connect to one computer
• Each user has a unique session
• Maintenance can be easy
• Requires a powerful computer
• Example: UNIX, Linux, etc,.
11. Time sharing OS
• It handles multiple jobs at a time.
• It switches the CPU among various jobs
that are running on the computer
whenever there is a program break or a
fixed time has expired.
12. Virtual storage OS
• It uses the technique Demand paging. i.e.
whenever the program size is larger than
the main memory it splits the program into
many pages.
• Only the needed page is loaded to the
main memory for execution.
13. Real-time operating system
• It gets data from an on going event.
• Respond quickly to user input.
• Example: Reservation system
19. OS
• It is a collection of programs that controls
and manages all the components present
in the computer
20. Device drivers
• It is set of programs, which act as an
interface between the computer and the
device.
• It is responsible for the proper functioning
of the device.
COMPUTER
D
R
I
V
E
R
S
DEVICE 1
DEVICE 2
DEVICE n
21. Language Processor
• It is a system s/w that translates the
programs written in High level language to
Machine language.
• Machine language: 0’s and 1’s.
• High level language: C, C++, Java etc,.
Example: Compiler, Interpreter, Assembler
22. Compiler
• It converts the programs written in high
level language to machine language i.e. it
translates the source code to object code.
HIGH LEVEL
LANGUAGE
C
O
M
P
I
L
E
R
MACHINE LANGUAGE
23. Interpreter
• It converts the programs written in high
level language to machine language.
• It executes the source code in line-by-line
manner. I
N
T
E
R
P
R
E
T
R
E
HIGH LEVEL
LANGUAGE
MACHINE LANGUAGE
24. Assembler
• It converts the programs written in
Assembly language to machine language.
A
S
S
E
M
B
L
E
R
ASSEMBLY
LANGUAGE
MACHINE LANGUAGE
25. System Utilities
• These programs performs tasks related to
the maintenance of computer
– Example: Disk clean-up.
26. APPLICATION SOFTWARE
• It is collection of programs that performs a
specific task.
– Customised
– General
27. APPLICATION SOFTWARE (Cont)
• Customised Application s/w
It is developed to meet the requirements of
limited user.
• General Application s/w
It is developed to meet the requirements of
many user.
28. S/W Terminologies
• Firmware
It is a software, which is permanently
stored on the memory
Eg: BIOS
• Open source
• It is software developed by some
programmers and released for public
use
• The programming code is available so
that the user can modify it.
29. S/W Terminologies (Cont)
• Freeware
• It is a copyrighted software which is
given away free by the owner.
• Commercial s/w
• It is developed by business
organizations to earn profit
46. EVOLUTION OF INTERNET
• In 1960 US Dept of Defense created a
network called ARPANET (Advanced
Research Project Agency Network).It is
the forerunner of today’s Internet.
• By 1970’s ARPA helped in the
development of TCP/IP (Transmission
Control Protocol/Internet Protocol) which
is used for transferring of data between
networks.
47. • In 1980’s National Science Foundation
(NSF) created the NSFNET.
• In 1980’s e-mail was introduced.
• In 1990’s the world wide web was
introduced.
48. Internet Terminology
• Webpage – It is an electronic document
which contains information.
• Website – It is a collection of related
WebPages.
• Homepage – It is starting point or
doorway to the website. It is also known as
the index page.
49. Internet Terminology (Cont)
• Web Browser or Browser – It is a
program that enables the user to access
the Webpage and displays the webpage
on the computer screen.
• Uniform Resource Locator (URL) –It is
the unique Address of the Webpage,
which is used to identifies its location on
the internet.
50. Internet Terminology (Cont)
• Hypertext – It refers to the text that
connects other documents.
• Internet Service Provider (ISP) - It
provides access to the internet to user.
• Web Server – It is a computer that
services the requests from the clients i.e.
web browser
51. Internet Terminology (Cont)
• Download - It is the process of receiving
data from a remote computer to the local
computer.
• Upload – It is process of sending data
from local computer to remote computer.
52. Getting connected to the Internet
Requirements
• Modem
• A Connection with the ISP
53. IP Address
• The Internet Protocol Address is used for
identifying the computer.
• It can be expressed in dotted decimal form
or binary form.
• It has four octets i.e. it has four 8 bit
number Eg: 175.192.0.1
10101111.11000000.00000000.00000001
54. DNS
• Domain Name System
• It is used to maps the text to the IP
Address.
55. URL
• Uniform Resource Locator.
• It contains the protocol name, domain
name etc,.
• Eg: http://www.microsoft.com
56. Internet Application
• World Wide Web
It is a collection of information or
collection websites.
• e-mail
It is used to send electronic
message to anyone.
57. Internet Application (Cont)
• Chatting
• It is online Conversation.
• It is used to send message back and
forth to anyone.
• Remote Access
• It is the process of accessing
information present in a remote
computer.
58. Internet Application (Cont)
• File Sharing
• It enables a group of user to share
information.
• The information has been placed on a
shared location and the user access
the information.
59. Internet Application (Cont)
• IRC
• Internet Relay Chat.
• It is designed for group communication.
• Video Conferencing
• It allows two or more user to interact via
video and audio transmission.
60. Internet Application (Cont)
• FTP
• File Transfer Protocol
• It is used to transfer data from one
computer to another computer.
• TelNet
• Telecommunication Network
• This protocol is used to get services
from the server.
