1. Introduction to Computing Lecture 9,10 Software

2. Software
Definition:
“A set of instruction to solve a particular problem”
“A piece of software is a computer program which has been written to carry out a particular task.”
Software programs are originally produced by computer programmers who will write the instructions that form the program in a programming language.

3. Types of Software A software is usually classified as being two types
Systems software
Applications software.

5. Types of Software Computer Application Software General- Purpose
Programs
Application-
Specific
System
Management
Development
Application
Software
Computer

6. Systems software Systems software controls the operation of a computer
Enables the other application programs to execute.
Without systems software a computer would not function.

7. System S/W Types System software divided in to two main types
System management programs
System development programs

8. System management programs
Examples
Operation systems(will be discus later in details)
Device drivers
BIOS Programs
Utility program

9. Operating System:
Operating System is a software, which makes a computer to actually work.
It is the software that enables all the programs we use.
The OS organizes and controls the hardware.
OS acts as an interface between the application programs and the machine hardware.
Examples: Windows, Linux, Unix and Mac etc.,

10. Device Drivers
Device drivers are computer programs allowing higher-level computer programs to interact with a hardware device.
A driver typically communicates with the device through the computer bus or communications subsystem to which the hardware connects.
Drivers are hardware-dependent and operating-system-specific.

11. Basic Input / Output System (BIOS)
Computer and Information Technology for HKCEE
Basic Input / Output System (BIOS)
BIOS is responsible for starting the PC
Boot the computer by providing a basic set of instructions.
Load the operating system after turning on the computer
Provide low-level routines for the communications between OS and hardware devices
DVEP

12. Utility Programs
A utility program allows a user to perform maintenance-type tasks usually related to managing a computer.
File and hard disk management for efficiency and storage.
Setting peripheral devices to the users requirements, i.e. setting the monitor resolution

13. Some Examples
Disk defragmenters :
Can detect computer files whose contents are broken across several locations on the hard disk, and move the fragments to one location to increase efficiency.
Network utilities:
Analyze the computer's network connectivity, configure network settings, check data transfer or log events

14. Disk cleaners:
Can find files that are unnecessary to computer operation, or take up considerable amounts of space. Disk cleaner helps the user to decide what to delete when their hard disk is full.
Backup
Can make a copy of all information stored on a disk, and restore either the entire disk (e.g. in an event of disk failure) or selected files (e.g. in an event of accidental deletion).

15. System development programs
Compiler:
A compiler is a program that reads a program in one language – the source language and translates into an equivalent program in another language (Machine language).
Source Languages
C++ language
FORTRAN language
Pascal’ language, etc
Machine languages
Assembly Language

16. Linkers can take objects from a collection called a library.
A linker or link editor is a program that takes one or more objects generated by compilers and assembles them into a single executable program.
Linkers can take objects from a collection called a library.
The objects are program modules containing machine code and information for the linker.
The linker takes care of arranging the objects in a program's address space.

17. Application software
Application software consists of programs designed to perform specific tasks for users to sport :
Home Activities,
Personal Activates,
Business Activates,
And Educational Activities;

18. Application S/W Types
Application software divided in to two main types
Custom based software/Application Specific Programs
Generic software/General-Purpose Programs

19. Custom based software
The software which is specified by the software vendor/producer for a specific organization or institute is called custom based software”
This is a software that is designed and developed for particular customer.
Example:
NADRA registration System
Railway Reservation system
Nobal Pharmacy Management system
And many more…….

20. Generic software It is design for general public uses.
Developed for the sale of to the software developers /users for their use.
The most common generic software packages are:
Word Processor
Presentation Software
Spreadsheets
Media players
Graphic designing software
And many more examples

21. Examples: Microsoft Word and WordPerfect
Word Processors:
Word processing is a tool that helps user in creating, editing, and printing documents. Word processors will normally have the following capabilities built into them: 
Spell checking
Standard layouts for normal documents
Have some characters appear in bold print, italics, or underlined
Save the document so it can be used again
print the document.
Examples: Microsoft Word and WordPerfect

22. WordPerfect

23. Budgets Payrolls Grade Calculations
Spreadsheets: The spreadsheet packages are designed to use numbers and formulas to do calculations with ease. Examples of spreadsheets include:
Budgets
Payrolls
Grade Calculations
The most commonly used spreadsheet programs are Microsoft Excel and Lotus 123.

24. Lotus 123

25. Graphic Presentations:
The presentation programs can make giving presentations and using overheads easier.  Other uses include: 
Slide Shows
Repeating Computer Presentations on a computer monitor
Using Sound and animation in slide shows 
The most recognized graphic presentation programs are Microsoft PowerPoint and Harvard Graphics.

26. Other Software: Bespoke:
Software that is specially written for an application.
An expensive but a perfect solution to a requirement when there is no suitable package available.
Often a one off piece of software written for a large organisation as a perfect match to their needs.

27. Air Traffic Control Software
is an example of Bespoke
Software.

28. Open source software (OSS):
OSS is computer software whose source code is available under a license that permits users to use, change, and improve the software, and to redistribute it in modified or unmodified form.
It is often developed in a public, collaborative manner.
Well-known OSS products are Linux, Apache, etc.,

29. Proprietary Software:
Proprietary software (also called non-free software)
Software with restrictions on using, copying and modifying as enforced by the proprietor.
Restrictions on use, modification and copying is achieved by either legal or technical means and sometimes both.
Proponents of proprietary software are Microsoft.
Ex: Microsoft Windows, RealPlayer, Adobe Photoshop, Mac OS, WinZip. , Nortan Antivirus etc.,

30. Sometimes more than one program is required to complete a task.
software package:
Sometimes more than one program is required to complete a task.
When this is the case the group of programs which together complete the task are known as a software package.
Multiple software programs that work together (or performs similar functions) and is bundled and sold together as a software package.

32. Q?