What is Software .
Types of Software .
What is Operating System .
Structure of Operating System .
Functions of Operating System .
Types of Operating System .
Examples of Operating System .
2. ❖ What is Software .
❖ Types of Software .
❖ What is Operating System .
❖ Structure of Operating System .
❖ Functions of Operating System .
❖ Types of Operating System .
❖ Examples of Operating System .
Learning Objectives :-
4. What is Software ?
❖ Software is a set of programs and a program is a sequence
of instructions written to solve a particular problem .
❖ Example VLC is a media player Software and we use VLC to
play the music and without media player we can’t play
music in computer like this to start a computer it required
operating system and operating system also example of
software without operating system computer is useless .
❖ Software is Binary Executable file (exe or bin) .In next slide
we see how binary executable file is created .
❖ They are Two types of software :-
➢ System Software
➢ Application Software
System Software
Application Software
6. How Executable file Create :-
❏ Source Code :- A sequence of instructions written to solve a particular problem. In
previous example sample.c is source code file .
❏ Compiler :- A compiler is a special program that processes instructions written in a
particular programming language and turns them into machine language that computer’s
processor understand .If any error in source code it display or else it create a Object file
with .obj extension .
❏ Object File :- A data file containing object code that is generated when a compiler
processes . In previous example sample.obj is object file .
❏ Linker :-A linker is a computer program that takes one or more object files generated by a
compiler and it link to header file which use in program combines them into one and
create executable file .
❏ Executable File :-An executable file is perform particular task when run .
❏ Processor :- Processor is required to run particular executable file .
7. types of software :-
Application Software System Software
Application software is computer software
designed to help the user to perform specific
tasks.
System software is computer software designed to
operate the computer hardware and to provide a
platform for running application software.
It is specific purpose software. It is general-purpose software.
Application Software performs in a environment
which created by System/Operating System
System Software Create his own environment to
run itself and run other application.
It executes when required . It executes at boot time and remain in RAM until
power off .
Examples :- VLC Media Player, Microsoft Word Examples :- Windows 7,Linux
9. What is operating system ?
❖ In Simple Words, Operating system is manager who manage the all tasks of system .
❖ An operating system is system software and It is a program that controls the execution of
application program and acts as an interface between the user application and the machine
hardware .
❖ It is an integrated set of specialized programs used to manage overall system resources and
operations of the system.
❖ Computer operating systems perform basic tasks, such as recognizing input from the
keyboard, sending output to the display screen, keeping track of files and directories on the
storage drives, and controlling peripheral devices, such as printers.
❖ Operating system is loaded into memory when a computer a booted and remains active as
long as machine is up .
10. structure of Operating System :-
● Hardware :-Provides basic computing resources
○ CPU, memory, I/O devices
● Operating System :- Controls and Manage the use of resources
among various applications and users
● Applications :- Define the ways in which the system resources are
used to solve the computing problems of the users
○ Word processors, compilers, web browsers, database systems,
video games
● User :- People, machines, other computers
11. structure of Unix/linux like OS :-
● Layer 0 :- Hardware
● Layer 1 :- Kernel (linux)
○ Kernel is core part of an O.S
○ Kernel is interface between hardware and shell
and manage the resources like
■ process management
■ memory management
● Layer 2 :- Shell (bash)
○ Shell is interface between other application and
kernel .
● Layer 3 : Applications (vi editor)
12. difference between kernel and os :-
Operating System Kernel
Operating System is a system program. Kernel is an important part of the operating
system.
Operating System is an interface between user
and hardware of the computer.
Kernel is an interface between shell and hardware
of the computer.
In addition to the responsibilities of Kernel,
Operating System is responsible for protection
and security of the computer.
Responsibilities of Kernel is memory
management, process management, task
management, disk management.
13. Functions of Operating System :-
● Memory Management :− Keeps track of the primary memory, i.e. what part of it is in use by
whom, what part is not in use, etc. and allocates the memory when a process or program
requests it.
● Processor Management :− Allocates the processor (CPU) to a process and deallocates the
processor when it is no longer required.
● Device Management :− Keeps track of all the devices. This is also called I/O controller that
decides which process gets the device, when, and for how much time.
● File Management :− Allocates and de-allocates the resources and decides who gets the
resources.
● Security :− Prevents unauthorized access to programs and data by means of passwords
and other similar techniques.
14. Functions of Operating System :-
● Job Accounting :− Keeps track of time and resources used by various jobs and/or users.
● Control Over System Performance :− Records delays between the request for a service
and from the system.
● Interaction with the Operators :− Interaction may take place via the console of the
computer in the form of instructions. The Operating System acknowledges the same, does
the corresponding action, and informs the operation by a display screen.
● Error-detecting Aids :− Production of dumps, traces, error messages, and other debugging
and error-detecting methods.
● Coordination Between Other Software and Users :− Coordination and assignment of
compilers, interpreters, assemblers, and other software to the various users of the computer
systems.
15. Types of Operating System :-
● Batch operating system :-
○ The users of a batch operating system do not interact with the computer directly.
Each user prepares his job on an off-line device like punch cards and submits it to
the computer operator. To speed up processing, jobs with similar needs are
batched together and run as a group. The programmers leave their programs with
the operator and the operator then sorts the programs with similar requirements
into batches.
○ The problems with Batch Systems are as follows :-
■ Lack of interaction between the user and the job.
■ CPU is often idle, because the speed of the mechanical I/O devices is slower
than the CPU.
■ Difficult to provide the desired priority.
17. Types of Operating System :-
● Time-sharing operating systems :-
○ Time-sharing is a technique which enables many people, located at various terminals, to use a
particular computer system at the same time. Time-sharing or multitasking is a logical
extension of multiprogramming. Processor's time which is shared among multiple users
simultaneously is termed as time-sharing.
○ The main difference between Multiprogrammed Batch Systems and Time-Sharing Systems is
that in case of Multiprogrammed batch systems, the objective is to maximize processor use,
whereas in Time-Sharing Systems, the objective is to minimize response time.
○ Multiple jobs are executed by the CPU by switching between them, but the switches occur so
frequently. Thus, the user can receive an immediate response.
○ The operating system uses CPU scheduling and multiprogramming to provide each user with a
small portion of a time. Computer systems that were designed primarily as batch systems have
been modified to time-sharing systems.
18. Types of Operating System :-
● Advantages of Time sharing operating systems
are as follows :-
■ Provides the advantage of quick
response.
■ Avoids duplication of software.
■ Reduces CPU idle time.
● Disadvantages of Time-sharing operating
systems are as follows :-
■ Problem of reliability.
■ Question of security and integrity of
user programs and data.
■ Problem of data communication.
19. Types of Operating System :-
● Distributed operating System :-
○ Distributed systems use multiple central processors to serve multiple real-time applications
and multiple users. Data processing jobs are distributed among the processors accordingly.
○ The processors communicate with one another through various communication lines (such as
high-speed buses or telephone lines). These are referred as loosely coupled systems or
distributed systems. Processors in a distributed system may vary in size and function. These
processors are referred as sites, nodes, computers, and so on.
○ The advantages of distributed systems are as follows −
■ With resource sharing facility, a user at one site may be able to use the resources
available at another.
■ Speedup the exchange of data with one another via electronic mail.
■ If one site fails in a distributed system, the remaining sites can potentially continue
operating.
■ Reduction of delays in data processing.
■ Reduction of the load on the host computer.
21. Types of Operating System :-
● Network operating System :-
○ A Network Operating System runs on a server and provides the server the capability to
manage data, users, groups, security, applications, and other networking functions. The
primary purpose of the network operating system is to allow shared file and printer access
among multiple computers in a network, typically a local area network (LAN) .
○ Examples of network operating systems include Microsoft Windows Server 2003, Microsoft
Windows Server 2008, UNIX, Linux, Mac OS X, Novell NetWare, and BSD.
○ The advantages of network operating systems are as follows −
■ Centralized servers are highly stable.
■ Security is server managed.
■ Upgrades to new technologies and hardware can be easily integrated into the system.
■ Remote access to servers is possible from different locations and types of systems.
○ The disadvantages of network operating systems are as follows −
■ High cost of buying and running a server.
■ Dependency on a central location for most operations.
■ Regular maintenance and updates are required.
23. Types of Operating System :-
● Real Time operating System :-
○ A real-time system is defined as a data processing system in which the time interval
required to process and respond to inputs is so small that it controls the environment.
The time taken by the system to respond to an input and display of required updated
information is termed as the response time. So in this method, the response time is very
less as compared to online processing.
○ Real-time systems are used when there are rigid time requirements on the operation of a
processor or the flow of data and real-time systems can be used as a control device in a
dedicated application. A real-time operating system must have well-defined, fixed time
constraints, otherwise the system will fail. For example, Scientific experiments, medical
imaging systems, industrial control systems, weapon systems, robots, air traffic control
systems, etc.
