The document provides an overview of computer software, defining it as a set of instructions enabling hardware functionality, categorized into system and application software. It describes various types and functions of operating systems, including process and memory management, and outlines different operating system models. Additionally, it highlights programming languages and their generations, emphasizing the importance of proper referencing for students in their assignments.

1. Unit 4: Computer Software
(4 Hrs)
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2. Unit 4: Computer Software (4 Hrs)
Introduction and types of software;
Definition and functions and types of
operating system; Programming
languages and their types.
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3. What is software?
• a set of instructions or programs that tell a computer how to perform
specific tasks.
• consists of code written in a programming language that is executed
by a computer's central processing unit (CPU) to carry out desired
functions.
• Software plays a crucial role in enabling hardware components to
perform various tasks and provide functionality to users.
• There are two main categories of software:
1. system software
2. application software.
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4. Types of software
•Computer Software
1. System software
• Operating System Software
• Device Driver
• Utility Software
• Language Translator
2. Application software
• Packaged Software
• Customized or Tailored Software
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5. Operating system
•An operating system (OS) is system software that acts as an interface
between computer hardware and the user. It provides a platform for
running applications and managing the resources of a computer
system.
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6. Where OS lies?
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7. System software
•a type of computer software designed to provide a platform for other
software to run and interact with the hardware of a computer system.
•It serves as an intermediary between the user and the computer
hardware, managing the fundamental operations of the computer
and providing a foundation for application software.
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8. Application Software
• known as "applications" or "apps," refers to a set of computer
programs designed to perform specific tasks or functions for
end-users.
•Unlike system software, which provides a platform for the computer's
basic functions, application software is developed to address the
diverse needs and requirements of users.
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9. Program vs software
Program Software
A program is a set of instructions written in a specific
programming language to perform a particular task or
set of tasks.
Software covers the programs, libraries,
documentation, and any other data or information
that can be used by a computer.
It can be a single application or a collection of related
applications designed to work together.
configuration files, documentation, and media files
C, C++ VLC media player, Adobe Reader
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10. Operating system
•software program that serves as an intermediary between computer
hardware and the computer user. It provides a set of essential
services and functionalities that allow other software applications to
run and interact with the computer's hardware components.
•Examples:- Microsoft Windows, macOS, Linux, Unix, Android, iOS,
Chrome OS
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12. History of OS:
Generation Time Period Features
First Generation (1940’s-1950’s) -No OS
-users directly interacted with hardware
Second Generation (1950’s-1960) -Batch Processing Systems
-Operating Systems: for the UNIVAC I
and the IBSYS for the IBM 709.
Third Generation (1965-1980)//(1960s-1970s) -Time-Sharing Systems
-Multiprogramming
-spooling
Fourth Generation (1970s-1980s) -Microprocessor Revolution
-DOS
Fifth Generation 1980s- Present -GUIS-macOS, Microsoft Windows
-Networked systems-Netware and
windows NT
-Open source system-Linux
Mobile OS
Virtualization
-Cloud computing-(AWS, Azure)
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13. Functions of OS
• Process Management:
• Memory Management:
• File System Management:
• Device Management:
• Security and Protection:
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14. Memory Management:
• Memory Allocation: Allocates and deallocates memory space as needed by
programs.
• Virtual Memory: Manages the use of both main memory and secondary
storage to provide an illusion of a larger amount of RAM than physically
available.
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15. File System Management:
• File Creation/Deletion: Manages the creation and deletion of files and
directories.
• File Access Control: Controls access to files and directories based on
permissions.
•
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16. Device Management:
• Device Drivers: Provides a consistent interface for different hardware devices.
• Input/Output Management: Manages input and output operations between
the computer and its peripherals.
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17. Security and Protection:
• User Authentication: Ensures that only authorized users can access the
system.
• Data Protection: Implements mechanisms to protect data integrity and
confidentiality.
• Access Control: Regulates access to resources and data based on user
privileges.
•
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18. Process Management:
• Process Scheduling: Determines which programs run in what order and for
how much time.
• Process Execution: Manages the execution of processes by allocating
resources and controlling their execution.
•
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19. Types of operating system
• Batch Operating system
• Time-sharing operating system
• Multitasking operating system
• Multiprocessing operating system
• Single-User, Single-Tasking Operating Systems
• Single-User, Multi-Tasking Operating Systems:
• Multi-User Operating Systems:
• Real-Time Operating Systems (RTOS):
• Distributed Operating Systems:
• Network Operating Systems:
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20. Single-User, Single-Tasking Operating
Systems:
• Designed for a single user and can handle only one task at a time.
• Examples include early versions of MS-DOS.
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21. Single-User, Multi-Tasking Operating
Systems:
• Allows a single user to run multiple applications or processes simultaneously.
• Examples include modern desktop operating systems like Windows, macOS,
and Linux.
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22. Multi-User Operating Systems:
• Supports multiple users simultaneously, each with their own independent
session.
• Used in server environments and mainframes.
• Examples include Unix, Linux, and various mainframe operating systems.
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23. Real-Time Operating Systems (RTOS):
• Designed for applications with strict timing and response requirements.
• Used in embedded systems, control systems, and robotics.
• Examples include VxWorks, QNX, and FreeRTOS.
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24. Distributed Operating Systems:
• Manages a group of independent computers as if they were a single system.
• Enables resource sharing and communication between distributed nodes.
• Examples include Amoeba and Google's Fuchsia.
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25. Network Operating Systems:
• Designed for network environments and facilitate communication and
resource sharing among connected devices.
• Examples include Novell NetWare and Microsoft Windows Server.
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26. Embedded Operating Systems:
• Tailored for specific embedded devices with limited resources.
• Used in devices like routers, set-top boxes, and IoT devices.
• Examples include Embedded Linux, FreeRTOS, and Windows Embedded.
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27. Open Source Operating system
•a type of operating system whose source code is made available to
the public, allowing anyone to view, modify, and distribute the code.
This means that the underlying code of the operating system is
transparent and accessible to anyone interested in examining or
contributing to its development.
•The philosophy behind open source promotes collaboration,
community-driven development, and the free distribution of
software.
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28. Examples of Open source OS
•Linus
•Berkeley Software Distribution(BSD)—derived from UNIX
•GNU/Linux
•ReactOS
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29. Programming languages
•Computer language
•Standardized communication technique for giving instructions to a
computer
•Set of semantic and syntactic rules.
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30. Types of Programming Languages
Generation Programming language
First Generation -Machine level language.
Second Generation -Assembly Level Language.
-Low level language
-mnemonics
Third generation -High Level Language
-FORTRAN-ALGOL-BASIC-COBOL-C/C++
Fourth Generation -Non-procedural languages
-general purpose programming language
-DBMS concept evolve
-PowerBuilder-XBASE-CSS-ColdFusion
Fifth Generation -focus on constraint programming
-Artificial Intelligence
-Artificial Neural Network
-Mercury-Prolog-OPS5
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31. Note:
•Students need to take these slides as only reference.
•Book need to be preferred and assignment should be done by
following book as well as slides, using own words.
•Paraphrasing is allowed but copying answers from other’s not allow.
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