© Paradigm Publishing Inc. 4-1 OPERATING SYSTEMS

© Paradigm Publishing Inc. 4-2 The Function of System Software What is the function of system software? –tells computer what to do and how to do it –issues instructions to perform actions in a certain order, allowing hardware to process data into information

© Paradigm Publishing Inc. 4-3 The Function of System Software Two Categories of Software –Application software includes programs that perform one task –System software controls the operations of a computer system

© Paradigm Publishing Inc. 4-4 The Function of the Operating System What is the function of the operating system? –manages main memory, or RAM –configures and controls peripheral devices – Ex. Mouse, keyboard –manages essential file operations –monitors system performance – Ex. Task manager –provides a user interface – Graphic or text

© Paradigm Publishing Inc. 4-5 The Function of the Operating System Booting a computer is a series of steps that displays the OS desktop on the screen.

© Paradigm Publishing Inc. 4-6 The Function of the Operating System Managing Memory –Throughput – a measure of computer’s performance –Buffers – hold information and data waiting to be transferred from input or output device –Print spooling – holds document in buffer until ready to be printed –Multitasking – working on two or more applications at the same time

© Paradigm Publishing Inc. 4-7 The Function of the Operating System Managing Memory –Driver enables the operating system to communicate with a peripheral device, such as a keyboard, monitor, mouse, modem, printer, or disk drive. –File manager maintains a record of all stored files and their locations, allowing a user to quickly locate and retrieve files. –Performance monitor checks the computer system’s speed and efficiency, as well as performance of CPU, memory, and storage disks.

© Paradigm Publishing Inc. 4-8 Software User Interfaces Graphical user interfaces use pictures or text symbols (icons) to stand for complex commands.

© Paradigm Publishing Inc. 4-9 Software User Interfaces Graphical User Interfaces –Desktop – screen on which graphical elements are displayed –Display window – 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 –Common command icons – common actions such as opening, saving, or printing files

© Paradigm Publishing Inc Personal Computer Operating Systems Windows Operating System –Windows XP Professional – designed for fast, powerful computers with much memory and hard disk space –Windows Vista – improves security, helps diagnose and repair system problems, and makes networking easier –Windows 7 – improves security, improved efficiency

© Paradigm Publishing Inc Personal Computer Operating Systems Macintosh Operating System –Mac OS – has impressive graphics and ease of use –Mac OS 9 – better speech recognition, supports files up to 2 terabytes, provides for many users, allows file encryption, and supports voice-entered passwords –Mac OS X – uses UNIX operating system foundation

© Paradigm Publishing Inc Personal Computer Operating Systems IBM OS/2 –used mainly for business applications Linux –an open-source software program (programming code is free to the public)

© Paradigm Publishing Inc Other Operating Systems Server Operating Systems – Novell, Unix Mobile Device Operation Sytems – Ex. Android(Google), iOS (Apple), Windows Phone (Microsoft)

© Paradigm Publishing Inc Utility Programs and Translators –Utility programs and their functions

© Paradigm Publishing Inc Utility Programs and Translators –Utility programs and their functions (continued)

© Paradigm Publishing Inc On the Horizon Based on the information presented in this chapter and your own experience, what do you think is on the horizon?