1. INTRODUCTION TO SOFTWARE DEVELOPMENT (SOFTWARE ENGINEERING-I)
Course Instructor KASHIF IHSAN
Kashif Ihsan, Lecturer CS, MIHE

2. Kashif Ihsan, Lecturer CS, MIHE
Chapter # 01
Software & Software Engineering
Table of Contents:
Software
Types of Software
Characteristics of Software
Attributes of Software
Definition of System Engineering
Definition of Software Engineering
Kashif Ihsan, Lecturer CS, MIHE

3. Kashif Ihsan, Lecturer CS, MIHE
What is a software ?
A software is an instruction (computer program) or set of instructions that when executed provide desired functionality and result.
Kashif Ihsan, Lecturer CS, MIHE

4. Kashif Ihsan, Lecturer CS, MIHE
Types of Software
1. System Software
2. Application Software
Kashif Ihsan, Lecturer CS, MIHE

5. Kashif Ihsan, Lecturer CS, MIHE
System Software
The software that runs the computer.
The software that manages the hardware resources of a computer.
Without System Software, we can not run a computer.
It provides a platform for different applications/programs to run on computer.
Example: Operating Systems (Windows Xp, Vista, 7),
Kashif Ihsan, Lecturer CS, MIHE

6. Kashif Ihsan, Lecturer CS, MIHE
Application Software
The software that performs some user specific job.
The software that when executed provides the desired functionality and result.
A computer can run without application software.
Examples: MS Office, Media Players, Messengers, Web Browsers, etc.
Kashif Ihsan, Lecturer CS, MIHE

7. Types of Application Software
Basically there are two types of application software:
Generic Software
Customized Software
Kashif Ihsan, Lecturer CS, MIHE

8. Kashif Ihsan, Lecturer CS, MIHE
Generic Software
These are the stand alone system which are produced by a developed organization and sold in open market to any one who is able to buy them.
For example: MS Office, Games, etc.
Kashif Ihsan, Lecturer CS, MIHE

9. Kashif Ihsan, Lecturer CS, MIHE
Customized Software
These are the softwares which are designed for a specific person/party on demand.
The customized software meets the need of that specific group of users & is not a generalized software.
Kashif Ihsan, Lecturer CS, MIHE

10. Characteristics of Software
Software is a logical entity, it has certain distinguishable characteristics:
Software is engineered or developed, it is not manufactured in classical sense.
Software doesn't wear out.
Most of the software are custom build rather then being assembled from existing components.
Kashif Ihsan, Lecturer CS, MIHE

11. Kashif Ihsan, Lecturer CS, MIHE
Software Types
System software
Real-time software
Embedded software
Business software
Web-based software
Artificial intelligence software
and so on……
Kashif Ihsan, Lecturer CS, MIHE

12. Kashif Ihsan, Lecturer CS, MIHE
System Software
System software is a computer software designed to operate the computer hardware and to provide and maintain a platform for running application softwares.
Examples: Operating System, Compilers, etc.
Kashif Ihsan, Lecturer CS, MIHE

13. Kashif Ihsan, Lecturer CS, MIHE
Real time Software
Software program that control real world events as they occur.
For example: Air traffic control system.
Kashif Ihsan, Lecturer CS, MIHE

14. Kashif Ihsan, Lecturer CS, MIHE
Embedded Software
Software that resides in intelligent product and are used to control these products.
Examples: Keypad control of microwave oven, T.V remote control, etc.
Kashif Ihsan, Lecturer CS, MIHE

15. Kashif Ihsan, Lecturer CS, MIHE
Business Software
Business softwares are written to process business information.
Examples are payroll, quickbook, peachtree, etc.
Kashif Ihsan, Lecturer CS, MIHE

16. Kashif Ihsan, Lecturer CS, MIHE
Web-Based Software
Also called WEB APPLICATIONS.
An application software that is accessed over a network such as internet.
Java Applet in web browsers is the example of web application.
Kashif Ihsan, Lecturer CS, MIHE

17. Artificial Intelligence Software
The softwares inside intelligent devices such as robots that perceives its environment and take actions that maximize its chances of success are termed as Artificial Intelligence Softwares.
Kashif Ihsan, Lecturer CS, MIHE

18. Attributes of a Good Software
The software should deliver the required functionality and possess the following attributes:
1. Maintainability
2. Dependability
3. Efficiency
4. Usability
Kashif Ihsan, Lecturer CS, MIHE

19. Kashif Ihsan, Lecturer CS, MIHE
Maintainability
A software must be flexible enough to accommodate the changing needs and deliver accordingly.
Kashif Ihsan, Lecturer CS, MIHE

20. Kashif Ihsan, Lecturer CS, MIHE
Dependability
A software must be trustworthy and reliable to operate.
A software should be dependable all the time.
Kashif Ihsan, Lecturer CS, MIHE

21. Kashif Ihsan, Lecturer CS, MIHE
Efficiency
A software should be efficient.
It should not make a wasteful use of system resources.
Kashif Ihsan, Lecturer CS, MIHE

22. Kashif Ihsan, Lecturer CS, MIHE
Usability
A software should be usable by the users for which it was designed.
Kashif Ihsan, Lecturer CS, MIHE

23. Kashif Ihsan, Lecturer CS, MIHE
What is Engineering?
Any systematic (step by step) approach is known as engineering OR
Acting according to a plan
Kashif Ihsan, Lecturer CS, MIHE

24. Engineering in general
Engineering is the application of theories, tools and methods to find a solution to a problem with the constrain of work, organization and finance.
Kashif Ihsan, Lecturer CS, MIHE

25. Kashif Ihsan, Lecturer CS, MIHE
What is System?
The word system is derived from Greek word “systema” which mean an organized relationship among the functional units.
Kashif Ihsan, Lecturer CS, MIHE

26. Kashif Ihsan, Lecturer CS, MIHE
System
System is a collection of elements or components that work together to achieve some common goal. OR
A purposeful collection of inter-related components working together towards a common objective.
Kashif Ihsan, Lecturer CS, MIHE

27. Kashif Ihsan, Lecturer CS, MIHE
System Engineering
Software engineering occur as consequence of a process called a system engineering. Before a software development, we must engineer the “system” in which the software will work.
Kashif Ihsan, Lecturer CS, MIHE

28. Kashif Ihsan, Lecturer CS, MIHE
System Engineering
System engineering is concerned with all aspects of computer-based systems development including hardware, software and process engineering.
Software engineering is part of this process.
Kashif Ihsan, Lecturer CS, MIHE

29. Kashif Ihsan, Lecturer CS, MIHE
System Engineering
In system engineering, the overall objective of the system is determined. The role of hardware, software, users, database and other system elements are identified. Operational requirements are analyzed, specified, modeled, validated and managed.
Kashif Ihsan, Lecturer CS, MIHE

30. What is Software Engineering ?
There are a number of possible definitions of software engineering:
The application of a systemic, disciplined, quantifiable (scientific/experimental/proven) approach to the development, operation, and maintenance of software.
Kashif Ihsan, Lecturer CS, MIHE

31. What is Software Engineering ?
Software engineering is concerned with theories, methods and tools for professional software development
Kashif Ihsan, Lecturer CS, MIHE

32. What is Software Engineering ?
Software engineering is the use of engineering principles used for computer software development in order to obtain software that is reliable (good in quality which give result in all circumstances) and work efficiently.
Kashif Ihsan, Lecturer CS, MIHE

33. What is Software Engineering ?
Software engineers should adopt a systematic and organised approach to their work and use appropriate tools and techniques depending on the problem to be solved, the development constraints and the resources available.
Kashif Ihsan, Lecturer CS, MIHE

34. What is Software Engineering ?
Software does not simply mean the computer programs associated with some application or product.
As well as programs, ‘software’ includes the documentation necessary to install, use, develop and maintain these programs.
Kashif Ihsan, Lecturer CS, MIHE

35. What is Software Engineering ?
Software engineers should adopt a systematic and organized approach to their work and use appropriate tools and techniques depending on the problem to be solved, the development constraints and the resources available.
Kashif Ihsan, Lecturer CS, MIHE

36. Kashif Ihsan, Lecturer CS, MIHE
END OF CHAPTER # 01
Kashif Ihsan, Lecturer CS, MIHE