1. mazharjaved2001@yahoo.com(0333-4461420) Software Prepared By: Sir Mazhar Chapter No 5

2. mazharjaved2001@yahoo.com(0333-4461420) Software ► Logical Component of a Computer ► We can not touch ► These are in form of instructions that tell the computer that what to do ► It can not executed without hardware. ► If any problem in software then it will reinstall.

3. mazharjaved2001@yahoo.com(0333-4461420) Software Kinds ► Software may be in the form of ► System Software ► Application Software

4. mazharjaved2001@yahoo.com(0333-4461420) System Software ► It controls a computer’s internal function ► System software manages the fundamental operations of your computer  Operating system  Utilities  Library  Programming Languages ► It also control mouse,printer, Monitors ► Examples ► Operating System ► Language Software

5. mazharjaved2001@yahoo.com(0333-4461420) Operating System (OS) ► Is collection of System software ► An interface between applications and hardware ► Hardware needs a manager to tell it  what to do  when to do it  how to do it ► The (OS) controls all  input  output  Processing Uses ► It manages the data and the memory and appearance ► Make the computer system convenient to use ► Execute user programs and make solving user problems easier.

6. mazharjaved2001@yahoo.com(0333-4461420) Goals or Task ► Efficiency  Allows computer system resources to be used in an efficient manner ► Ability to evolve  Permit effective development, testing, and introduction of new system functions without interfering with service ► Communication with hardware  They provide the way for application software to communicate with hardware ► Transfer data  They manage the transfer of data to and from the various peripherals ► System Security  They manage system security. Many operating systems allocate certain rights to user

7. mazharjaved2001@yahoo.com(0333-4461420) User Interaction with OS Hardware Operating System Software Computer User

8. mazharjaved2001@yahoo.com(0333-4461420) Examples ► Window 98 ► Window 2000 ► Window XP ► Window Vista ► Linux ► Unix

9. mazharjaved2001@yahoo.com(0333-4461420) User interfaces ► User interface is what you see when you turn on the computer ► It consists of the cursors, prompts, icons and menus etc ► Which allow you to get something done using your computer ► Ideally the user interface should be as easy to use as possible User interface may be ► Command driven interface ► Menu driven interface ► Graphical user interface

10. mazharjaved2001@yahoo.com(0333-4461420) Command driven interface ► With a command driven interface, you type in an instruction, which is usually abbreviated, in order to get something done. ► Are not easy to use ► A set of commands used to interact with computer is called command language ► It requires exact spelling and punctuation ► Advantage: ► Commands for different software application are rarely the same so user can be faster to use and have learnt all the commands

11. mazharjaved2001@yahoo.com(0333-4461420) Menu driven interface ► The user enter data and instruction by using menus ► Easy to use because the user has not remember the syntax of commands ► User can make a selection by using either a mouse or a keyboard ► Drop down list ► Present options ► Both Microsoft Windows and Apple Macintosh programs are menu driven

12. mazharjaved2001@yahoo.com(0333-4461420) Graphical User Interface (GUI) ► Is a visual environment that is used by the user to communicate with computer ► It uses windows,icons, menus and other graphical objects to issue commands. ► Easy to use ► Easy to learn ► Attractive ► WIMP: stands for windows, and pointing devices which describes the features of GUI

13. mazharjaved2001@yahoo.com(0333-4461420) Disadvantages ► More immediate access store and secondary store ► More powerful processor and graphical card ► Slower then executing ► Greater no of operations is required

14. mazharjaved2001@yahoo.com(0333-4461420) Designing a user interface ► Consistency ► Positioning of items on the screen ► Use of colour ► Use of sound ► Availability of help

15. mazharjaved2001@yahoo.com(0333-4461420) Utility programs ► A type of system software that is used to solve particular problem. ► Designed to make life easier for computer users. Utility programs perform thousands of task ► Renaming files ► Listing file on a disk ► Deleting files ► Copying files ► Sending files to a printer ► Storing data ► Backing up files

16. mazharjaved2001@yahoo.com(0333-4461420) Examples File Viewer ► Is used to view and manage files in computer system. ► Window Explorer File Compressor: File Compressor: ► Is used to shrink the size of files ► Winzip and WinRAR Diagnostic Utilities: ► is used to detect problem in hardware and software ► AntiVirus ► Disk Defragmenter ► Backup utility ► Data Recovery Utility ► Task Manager utility ► Disk Cleanup ► Personal Firewall ► Spyware Remover

17. mazharjaved2001@yahoo.com(0333-4461420) Application Software ► Application software enables you to perform specific computer tasks, such as document production, spreadsheet calculations, and database management ► Any program that processes data for a user Users prepare these ► Packaged software ► Custom Software ► Integrated software ► Bespoke Software ► Shareware ► Free Ware ► Public Domain Software

18. mazharjaved2001@yahoo.com(0333-4461420) Integrated Software ► Single program ► Kind of a Jack-of-all-trades ► Shares a common set of commands ► Commands are common throughout ► Moving data from one program to another is easy ► Which combine features from all below products ► Multiple functionality  Word processor, spreadsheet, DBMS, Presentation graphics and communication software ► Advantages  Lower cost  Simpler  Capabilities not as extensive ► Disadvantages: ► Tend to be strong in one area and weak in others

19. mazharjaved2001@yahoo.com(0333-4461420) Application Packages ► It is particular user or organization. ► The program are well tested ► Is available for different types of users ► Documentation are very good ► Examples: ► Word processing software such as word and word perfect ► Spread sheet software such as Lotus 1-2-3 and Excel ► Data base software such as Access

20. mazharjaved2001@yahoo.com(0333-4461420) Tailor Made Software or Custom Software ► Is developed to meet the requirement of particular company or industry. ► If packaged software does not fulfill the requirement of an organization, it has to develop a custom software by hiring a programmer. ► The cost of custom software is higher.

21. mazharjaved2001@yahoo.com(0333-4461420) Program ► The instructions that tell the computer what to do is called program ► Programmer: ► Who writes or design the program in any language. ► Computer can understand only the binary code

22. mazharjaved2001@yahoo.com(0333-4461420) Programming Languages ► Humans can use different languages to communicate ► The instructions are written in a languages which are easy to understand ► Programming languages may be in the form of ► High level Languages ► Low Level Languages

23. mazharjaved2001@yahoo.com(0333-4461420) Low level languages ► Are languages that are easy for the computer to understand but more difficult for the programmer ► Each instruction usually translates into one machine code instruction

24. mazharjaved2001@yahoo.com(0333-4461420) Kinds of Low Level ► Machine Language ► Assembly Language

25. mazharjaved2001@yahoo.com(0333-4461420) Machine Language ► Is the language that directly understood by the machine ► It consists of series of a 0s and 1s ► It is a machine specific it mean that one computer’s machine code will not be understand by other computer type ► It needs no translation so that way it is very fast ► A lot of games or simulation programs are written in machine code for this reason

26. mazharjaved2001@yahoo.com(0333-4461420) Assembly language ► It is easier for the programmer to use and to debug ► Once a program has been written in assembly language it needs translating into machine code by software called assembler ► Is a low level language which allows the programmer to use Mnemonics and symbolic address ► Mnemonics: ► Is a word or set of letters which can be used to represent a function code and which is easy to remember ► Example: ► LDA use for Load Accumulation ► JMP for jump instruction and ADD are mnemonics ► Symbolic Address: ► Is a name inverted by the programmer to identify a location ► Loop,value and prnt are symbolic addresses

27. mazharjaved2001@yahoo.com(0333-4461420) High level language ► Is developed with the programmer in mind rather than the computer ► High level language instructions are similar to English which mean programming is more easier. ► Once a program has been written it can be used on different computers with little alteration ► It can be translated into machine code by a compiler and then run

28. mazharjaved2001@yahoo.com(0333-4461420) Advantages ► Simple instruction similar to English make high level language easy to understand ► It is easy to correct errors and test programs ► Programs written in high level language can be used on different makes of computer

29. mazharjaved2001@yahoo.com(0333-4461420) Different High Level Languages COBOL: COBOL: ► common business oriented language Purpose: ► easily understand language for commercial data processing application Features: ► look like English Statement ► Good facilities for file handling

30. mazharjaved2001@yahoo.com(0333-4461420) BASIC ► Beginners all purpose symbolic instruction code Purpose: ► Teaching language for interactive work Features: ► Every line has to be numbered ► Easy for beginners to learn ► Many different versions

31. mazharjaved2001@yahoo.com(0333-4461420) FORTON ► Formula translation Purpose : ► For scientific use. Usually batch work Features: ► Lacks of statements which makes program structure clear ► Designed to be used with cards as input and a line printer as a output

32. mazharjaved2001@yahoo.com(0333-4461420) Logo Purpose : ► An educational language that encourage logical thinking Features : ► New instructions can be added and can be defined ► Facilities to process lists

33. mazharjaved2001@yahoo.com(0333-4461420) Pascal Purpose : ► To allow clear structuring of data and program Features: ► All variables are declared before they can be used. ► Encourages clear structure and stepwise refinement ► New procedures,functions and data types can be defined and added in

34. mazharjaved2001@yahoo.com(0333-4461420) JAVA ► A language especially suited for writing software used to search for things on the internet. HTML HTML ► Hypertext markup language ► A language used for the development of websites

35. mazharjaved2001@yahoo.com(0333-4461420) Types of codes ► Source code ► Is written in high language or assembly language ► Easy to understand ► Easy to modify ► Contain fewer statements ► It contain.exe extension ► Object code ► Is written in machine language through compiler ► difficult to understand ► Difficult to modify ► More statement than source code ► It contain.obj extension

36. mazharjaved2001@yahoo.com(0333-4461420) Translation programs ► Are part of the system software and are used to convert the programs commands into machine code ► There are three types of translation program ► Compiler ► Interpreters ► Assemblers

37. mazharjaved2001@yahoo.com(0333-4461420) Compiler ► Is software that converts the whole of a program written in a high level language into machine code in one go. ► There are no mistakes in the program the complete program is converted to machine code ► If a program needs to be altered at a later date the original source code is altered and program recompiled

38. mazharjaved2001@yahoo.com(0333-4461420) Interpreter ► Each instructions in turn, converts it to machine code and then caries it out ► It run one line at a time ► The computer recognizes each instruction

39. mazharjaved2001@yahoo.com(0333-4461420) Differences ► Compiler ► Converts a program into a machine code as a whole ► Creates object code file ► Converts high level programs that can be executed in many times ► Execution is fast ► Displays syntax errors after compiling the whole program ► Interpreter ► Converts a program into machine code statement by statement ► Object file is not created ► Converts high level programs each time it is executed ► Program execution is slow ► Displays the syntax error on each statement of program

40. mazharjaved2001@yahoo.com(0333-4461420) Assembler ► Is a program which translates a program written in as assembly language into are in machine code ► The main functions of an assembler are to : ► Translate an assembly language source program into a machine code object program ► Work out where to store the object program and its data ► Detects errors in the source program and say what they are ► Link the program to any other programs or routines it uses ► Print a listing of the source and object programs

41. mazharjaved2001@yahoo.com(0333-4461420) Relationship Assembly Language Code High Level Language Code High Level Language Code InterpreterCompilerAssembler Machine Code