1 ITGS – Software Basic Food for Thought: Recipe for food Precise steps How many steps Processing with Programs 1

2 ITGS – Software Basic Food for Thought: One step to explain many actions Processing with Programs 2

3 ITGS – Software Basic Computers – smart or intelligent machines but they perform only basic arithmetic operations Computers – fast, smart machines

4 ITGS – Software Basic Algorithm is set of step-by-step procedures for accomplishing a task. Programmers turn algorithms into programs by adding details, testing procedures and debugging – correcting errors. Algorithm

5 ITGS – Software Basic Every computer processes instructions in a native machine language. Machine language uses numeric codes to represent the most basic operations- adding, comparing, moving numbers and repeating instructions. The Language of Computers 1

6 ITGS – Software Basic Early programs were written in machine language. Nowadays, programming languages are like human languages. High-level languages: C++, Java, Visual Basic.Net The Language of Computers 2

7 ITGS – Software Basic Computer understands only machine language. High-level languages are easy for use for human. High-level languages must be translated to the zeros and ones of machine language. A translator program 1

8 ITGS – Software Basic A translator program converts the English-like instructions to the zeros and ones of machine language. Translation process must be finished before using program. A translator program 2

9 ITGS – Software Basic A translator programs are divided: - compiler – translates file (formed.exe executive file). Complete translation before the first run (execution). - interpreter each time when its run translate instruction. (instruction by instruction) A translator program 3

10 Input Program (Source file) Compiler Output: Program (Exe file) ITGS – Software Basic Translation processes 4

11 Input Statement (each) Interpreter Output: Statement (each) ITGS – Software Basic Translation processes 5

12 ITGS – Software Basic Software package includes printed documentation Tutorial manuals Reference manuals (how to use software) Help (printed, on CD, DVD, computer or online) Documentation

13 ITGS – Software Basic New version Update: New versions Upgrading

14 ITGS – Software Basic No complete, universal software standards exist in computer world. Problem: program written for one type of computer system may not work on another. Windows 9x Compatibility 1

15 ITGS – Software Basic Software - Microsoft: DOS Windows Office (documents) Compatibility 2

16 ITGS – Software Basic Most programs works amazingly well but not perfectly. Disclaimers

17 ITGS – Software Basic Applications designed specifically for a particular business or industry are called vertical-market or custom applications. (restaurant-management software, medical-billing software, school evidence software) Cost far more then mass-market applications. Vertical Market and Custom Software

18 ITGS – Software Basic System software: Operating system (OS) Utility programs Links Compilers Operating system 1

19 ITGS – Software Basic Operating system (OS): Part of system software Work behind the scenes Operating system 2

20 ITGS – Software Basic Operating system communicating with: screens printers disk drives other peripheral devices OS communicate with peripherals and with user Operating system 3

21 ITGS – Software Basic Operating system - concurrent processing of jobs : Rapidly switching back and forth between jobs (waiting for input, or printer, …) Time sharing: OS Concurrent Processing of Jobs

22 ITGS – Software Basic Operating system communicating with: screens printers disk drives other peripheral devices OS communicate with peripherals OS Communicate

23 ITGS – Software Basic Several jobs concurrently: OS must keep track Divide memory Swap information between the computer’s memory and external storage devices (access time slower) Memory Management

24 ITGS – Software Basic Several jobs concurrently: OS must keep track Data Management

25 ITGS – Software Basic Utility programs serve as tools for doing system and repairs that aren’t automatically handled by the operating system. Copy files, repair damaged data files, translate files to different programs, compress files, … Operating systems invoke many utility programs Programs and Data Drivers

26 ITGS – Software Basic PC operating systems, created for the Apple II, the original IMB PC and other machines, looked nothing like today’s Macintosh and Windows operating systems. It was OS a character-based interface. A command line systems. Desktop Operating Systems 1

27 ITGS – Software Basic Graphic display; is not limited to displaying rows and columns of characters, it can individually control every dot on the screen. The MAC OS a graphical user interface- abbreviated GUI (gooey) Desktop Operating Systems 2

28 ITGS – Software Basic The first to market, the Macintosh was eclipsed in the GUI operating system. At the beginning MS Windows was a program (shell) that put graphical face on MS DOS. With Windows 95 MS transforming Windows from an operating system shell into full operating system. Desktop Operating Systems 3

29 ITGS – Software Basic Hierarchical menus in Windows Mac OS organization (frequently needed commands into compact). Pop-up menus Context-sensitive menus Desktop Operating Systems 4

30 ITGS – Software Basic Unix operating system developed at Bell Labs over a decade before the first PCs, enables a timesharing computer to communicate with several other computers or terminals at one time. UNIX is command line, character-based operating system. Multiple-User Operating systems: Unix and Linux

31 ITGS – Software Basic Using a Linux GUI Goal: GNOME, a shell that puts a graphical desktop environment between you and the Linux command-line environment. Tools: Linux, GNOME, OpenOffice

32 ITGS – Software Basic Hardware and Software Platforms 1 Microsoft Windows XP (2001) Home edition; home users Windows XP Professional (business users) Windows XP Tablet PC Edition (Tablet PC-style notebooks) Windows XP Media Center Edition (multimedia-enabled PCs)

33 ITGS – Software Basic Hardware and Software Platforms 2 Microsoft Windows XP is enhanced version of Windows 2000 Professional. Both Windows XP and Windows 2000 are technically successors to Windows NT, not Windows 9x/DOS.

34 ITGS – Software Basic Hardware and Software Platforms 3 Microsoft Server 2003 server-based counterpart to Windows XP successor to the Windows 2000 Server product family, runs on all sizes of Web servers.

35 ITGS – Software Basic Hardware and Software Platforms 4 Microsoft Windows Millennium Edition. (Windows Me)/Windows9x. The end of the DOS–based Windows versions. (Windows 3.1x; Windows 95; Windows 98;

36 ITGS – Software Basic Hardware and Software Platforms 5 Microsoft Windows CE.NET is designed mostly for embedded connecter devices, and a special versions of the OS, handheld computers like the Pocket PC.

37 ITGS – Software Basic Hardware and Software Platforms 6 Palm OS Mac OS X(20) Mac OS 9 Linux, Sun Solaris and other UNIX variants. Linux is free, but doesn’t offer applications programs as Windows does.

38 ITGS – Software Basic Hardware and Software Platforms 7 Operating systems need application software so they can do useful work. Application software needs to be built to any kind of platform. Platform is combination of hardware and operating system software. Cross-platform applications (MS Office, Photoshop, are available in similar versions for multiple platforms.

39 ITGS – Software Basic Hardware and Software Platforms 8 Three general platforms: Windows Mac OS (graphic design, publishing, music, video, multimedia) UNIX/Linux (servers and high-end workstations)

40 ITGS – Software Basic Hardware and Software Platforms 9 Three OS: Windows (Intel or compatible CPU) Mac OS (Power PC processors) UNIX/Linux (can run on many hardware platforms, including Intel and Power PC processors) but different versions of Linux aren’t necessarily compatible.

41 ITGS – Software Basic Hardware and Software Platforms 10 Emulation, blurs the line between platforms.

42 ITGS – Software Basic Hardware and Software Platforms 11 Network vs. desktop More time on the Web Microsoft’s.NET strategy is a response to the popularity of Java, a platform- neutral computer language developed. Program written in Java can run on different OS.

43 ITGS – Software Basic Password Changing letters Name of hacker programs used for getting in program How to keep security of password? (hardware, software)