Chapter 4 System Software

1. Chapter 4 System Software Chapter 4 System Software

2. Presentation Overview • The Function of System Software • The Function of the Operating System • Software User Interfaces • Personal Computer Operating Systems • Server Operating Systems • Operating Systems for Handheld Devices • Utility Programs and Translators

3. The Function of System Software What is the function of system software? • To tell the computer what to do and how to do it • To issue instructions to perform actions in a certain order, allowing hardware to process data into information

4. The Function of System Software There are two main categories of system software. • Application software includes programs that perform a single task. • System software controls the operations of a computer system.

5. The Function of the Operating System What is the function of the operating system? • To manage main memory, or RAM • To configure and control peripheral devices • To manage essential file operations • To monitor system performance • To provide a user interface

6. The Function of the Operating System Commonly Used Operating Systems for Personal Computers

7. The Function of the Operating System Booting a computer involves a series of steps that culminates with the display of the OS desktop on the screen.

8. The Function of the Operating System Managing Memory • Throughput is a measure of the computer’s overall performance. • Buffers hold information and data waiting to be transferred to or from an input or output device. • Print spooling holds a document in a buffer until the printer is ready. • Multitasking allows an individual user to work on two or more applications at the same time.

9. The Function of the Operating System • Configuring and Controlling Devices • A driver enables the operating system to communicate with peripheral devices. • Managing Essential File Operations • A file manager is a program that maintains a record of all stored files and their locations. • Monitoring System Performance • A performance monitor checks the computer’s speed, efficiency, and performance.

10. Software User Interfaces Command line interfaces require users to type a line of code at a prompt telling the computer what to do.

11. Software User Interfaces Graphical user interfaces use pictures or text symbols (icons) to stand for complex commands.

12. Software User Interfaces Features of Graphical User Interfaces • Desktop – the screen on which graphical elements are displayed • Display window – an area of the screen used to display a program or data • Menu – set of options that can be activated with the click of a mouse • Command icons – represent common actions such as opening, saving, and printing files

13. Personal Computer Operating Systems Windows Operating System • Windows 2000 – used for business and network computers • Windows XP – designed for fast, powerful computers with much memory and hard disk space • Windows 7 – released in late 2009; requires powerful hardware to run; features faster boot and shut down times

14. Personal Computer Operating Systems Macintosh Operating System • Mac OS – first commercial GUI; has impressive graphics and ease of use • Mac OS 9 – offers better speech recognition than OS; supports files up to 2 terabytes; provides for multiple users • Mac OS X – introduced an interface called Aqua; uses UNIX operating system foundation

15. Personal Computer Operating Systems • IBM OS/2 • runs programs written for DOS and Windows systems • used mainly for business applications • Linux • an open-source software program (programming code is free to the public) • praised for stability, flexibility, security, and low cost

16. Server Operating Systems Novell Netware and Open Enterprise Server • Netware was widely used for local area networks; it was replaced by OES in 2005. • Both operating systems • Allow retrieval or saving of files from server’s shared hard disk • Allow printing using a shared printer • Offer the option of working with or without network resources

17. Server Operating Systems Windows • Windows 2000 Server – provided for Internet access and the development of Web pages • Windows Server 2003 – offered in four editions to support different sizes of businesses • Windows Server –has Windows Vista benefits and offers server-specific tools, protocols, and utilities for network management

18. Server Operating Systems UNIX and Linux • UNIX – a cross-platform system that runs any type of computer from PC to supercomputer • Linux – an open-source software program designed for use with servers and large computer systems, including midrange servers and mainframes

19. Operating Systems for Handheld Devices • Palm OS • provides a graphical user interface used in various versions of Palm PDAs, Sony PDAs, and smartphones • Windows Mobile • used in wireless devices and other systems with embedded processors, such as smartphones and PocketPC PDAs

20. Utility Programs and Translators Utility Programs and Their Functions

21. Utility Programs and Translators Utility Programs and Their Functions (continued)

22. Utility Programs and Translators Utility Programs and Their Functions (continued)

23. Utility Programs and Translators Firewalls prevent unauthorized users from accessing a personal computer or network connected to the Internet.

24. Utility Programs and Translators • Shown is a simple payroll program written in DOS BASIC, a high-level language. • High-level languages must be translated into machine-language format before the CPU can execute them.

25. On the Horizon Based on the information in this chapter and your own personal experience, what do you think is on the horizon?