2. Computer System can be think of two
parts:-
• Hardware:-Which performs all the
computation and calculation work that
computers are known for
• Software:-Which instructs the hardware
what to do and how to do it.
4. Computer understand two concepts-On or Off,
which is basis for binary language.
Hardware needs a software(a set of programs)
to instruct what has to be done.
A program is a set of instructions that is
arranged in a sequence to guide a computer to
find a solution for the given problem.
Process of writing a program is called
programming.
Programs written by the programmer using a
programming language are also called source
code.
5. Computer Games-Entertainment software
Driver Software
Educational Software:- e.g. Interactive
geometry software, Language learning
software
Media Players
Productivity Software:-e.g. Presentation
Software
Operating System Software :-e.g. Window
Vista, Linux
6. There are two types of Software
1. Application Software
2. System Software
7. Designed for user to solve a particular
problem
It represent programs that allow users to do
something.
E.g. Spreadsheets, Database systems, games,
Web Browsers
8. Provides a general programming environment
in which programmer can create applications
to suit their needs.
It represent the programs that allow the
hardware to run properly.
Act as a interface between hardware of the
computer & application Software that user
need to run on the computer.
E.g. Operating System
9. User 1 User 2 User n
Application Programs
System Software
Computer Hardware e.g. printer,
mouse,keyboard
10. System Software Application Software
Collection of programs that enable Collection of programs written for
users to interact with hardware a specific application e.g. library
components system
Controls and manages the Uses the services provided by
hardware system software to interact with
hardware components
It is machine dependent It is Machine independent
Programmer must understand the Mostly programmer ignores the
architecture of machine and h/w architecture of machine and h/w
details to write it details to write it
It interact with h/w directly It interact with h/w indirectly
through system calls
Writing it is a complicated task Writing it is relatively easy
11. Designed to operate Computer h/w and
provide a platform for running application
s/w.
Most widely used system software types are:
Computer BIOS
Operating System
12. It provide basic functionality to operate &
control h/w connected to or built in the
computer.
BIOS is the first code run by computer when it
is switched on.
Key role of BIOS is to load the Operating
System.
When the computer starts, the code in the
BIOS chips run a series of tests called
POST(Power On Self Test) to ensure that
system devices are working properly.
13. BIOS chips locates the software held on other
devices like CD or Hard Disk, & loads and
executes that software, giving it the control
of Computer. This process is called Booting.
14. In short BIOS perform the following functions
Initialize the system Hardware
Initialize the system Registers
Initialize Power Management System
Test RAM
Test all the serial & parallel Ports
Display the system summary information.
15. The interface between the user and the computer hardware.
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.
16. User interface
User interact with operating system
Kernel
Core of operating system, responsible for loading
operating system
17. Intermed
Job iator Process
Scheduling Mgmt
Functions of
OS
File
Security
Mgmt
Memory
18. Intermediator: Facilitates easy communication
between the computer system and the computer
operator (human). It also establishes data
security and integrity.
Process Mgmt: that is, assignment of processor
to different tasks being performed by the
computer system.
File Mgmt: that is, the storage of file of various
storage devices to another. It also allows all files
to be easily changed and modified through the
use of text editors or some other files
manipulation routines.
19. Memory Mgmt: that is, allocation of main
memory and other storage areas to the system
programs as well as user programs and data.
Security: Operating systems provide password
protection to keep unauthorized users out of the
system.
Job Scheduling: it determines and maintains
the order in which jobs are to be executed in the
computer system.
21. GUI - Short for Graphical User Interface, a
GUI Operating System contains graphics
and icons and is commonly navigated by
using a computer mouse.
Example
22. Multi-user - A multi-user operating system
allows for multiple users to use the same
computer at the same time and/or different
times.
Example: LINUX
23. An operating system that is capable of
allowing multiple software processes to run
at the same time.
Below are some examples of multitasking
operating systems.
Unix
Windows XP, Vista
24. An operating system capable of supporting
and utilizing more than one computer
processor.
more than one CPUs that can be shared
Below are some examples of multiprocessing
operating systems.
Linux
Unix
Windows 2000
25. Smaller parts of a program are loaded when needed by
OS
Operating systems that allow different parts
of a software program to run concurrently
Operating systems that would fall into this
category are:
E.G
Linux
Unix
Windows 2000
26. DESKTOP
SERVER
MOBILE
DESKTOP
Types
of OS
MOBILE SERVER
28. By MICROSOFT co-operation
Advantages Disadvantages
Easy to use expensive
Familiar Update
Windows
Windows
Not stable Not secure
Gaming Supporting
29. By APPLE Co-operation
Advantages Disadvantages
Great Not
GUI gaming
Better to Not all
Stable Mac graphic expensive Mac software
run
designer
Difficult
mouse
Secure
(one click)
30. Advantages Disadvantages
Not all
Free
software
run
Low pc
Stable
requirement
Linux
Linux
Hard to
Not
Source Code Secure learn, use
support
and install
31. Server operating systems are designed to provide platforms for
multi-users , for critical, network applications. Their main
purpose is to provide security, stability and collaboration.
Most of them come with a pack of dedicated software tools
such as Web servers, e-mail agents and terminal services
The common applications for server OS are:
File and printer sharing
Application services (including databases)
Web site services
E-mail, groupware and messaging
Terminal services
Caching
33. operating system that controls a mobile device
Mobile OS
Symbian RIM Windows
iPhone OS Linux Palm OS BADA
OS BlackBerry Mobile
34. As Operating System controls and coordinates
the use of the hardware among the various
applications programs for various uses, we can
say that it plays a very important role in
computer system.
