Chapter 5The Operating System and the User Interface

Peter Norton’s Introduction to Computers

Learning Objectives:• Define the terms “operating system” and “user interface.”

• Name three major functions of the operating system and explain the importance of each function from the user’s perspective.

• List five types of utility software and describe how each can be used to enhance the functionality of an operating system.

• Define the term “multitasking” and list two ways it saves time for a user.

• List three other significant operating systems, aside from DOS and Windows.

Operating System(OS) - provides an interface for the user, software, hardware, and file management.

Functions of the Operating System:

• Provides the instruction to display the on-screen elements with which you interact.

• Loads programs into the computer’s memory so that you can use them.

• Coordinates how programs work with the CPU, RAM, keyboard, mouse, printer, and other hardware as well as with other software.

• Manages the way information is stored on and retrieved from disks.

Operating Systems:• DOS• Windows 95• Windows 98• Windows NT• OS/2 Warp• Mac OS• UNIX

DOS uses a command-line interface.

Windows 98 features the Active Desktop.

A single user interface allows a user to browsethe internet and the local computer resources.

Graphical User Interface (GUI) - (pronounced “gooey”) Uses graphics (icons) to represent commands and programs which are chosen using a mouse.

Icon - a graphic that represents printers, fonts, document files, folders, and so on.

Most people like icons because it’s easy tounderstand them and remember what they do.

Factors When Upgrading Your Operating System:

• CPU Type

• Memory

• Disk Space

• Compatibility

Operating System Services:• Saves the contents of files to a disk for permanent

storage.• Reads the contents of a file from disk into memory.• Sends a document to the printer and activates the

printer.• Provides resources that let you copy or move data

from one document to another, or from one program to another.

A hierarchical file system

Files can be managed with Windows Explorer.

Operating System Services:

• Allocates RAM among various programs that you may have open.

• Performs the seemingly simple activity of recognizing keystrokes or mouse clicks and displaying characters or graphics on the screen.

The operating system acts as an intermediarybetween the software and the hardware.

O.L.E. (Object Linking and Embedding - data is copied from one type of document and embedded into another. The data that is copied retains a link with the original document.

Multitasking - means being able to perform two or more procedures at the same time--such as printing a multipage document, sending e-mail over the Internet, and typing a letter--all simultaneously.

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Interrupt Request (IRQ) - used by the operating system to send requests to use memory and other hardware devices attached to the computer system.

Operating System Utilities:

• File Defragmentation

• Data Compression

• Backup Software

• Data Recovery Software

• Antivirus Utilities

• Screen Savers

Defragmenting the hard drivecan make file access faster.

Learning Objectives:Chapter 5 Review

• Define the terms “operating system” and “user interface.”

• Name three major functions of the operating system and explain the importance of each function from the user’s perspective.

• List five types of utility software and describe how each can be used to enhance the functionality of an operating system.

• Define the term “multitasking” and list two ways it saves time for a user.

• List three other significant operating systems, aside from DOS and Windows.