Chapter 4: continued

Software Bundles:

Vertical-market and Custom Software

-tends to cost far more than mass-market applications

-Job specific software:

• medical billings
• library cataloging
• legal reference software
• restaurant management
• software needs

System Software:

a class of software that includes the operating system and utility programs, handles these details, and hundreds of other tasks behind the scenes.

operating system functions:

• supports multitasking
• manages virtual memory
• maintains file system
• responsible for authentication and authorization

What is the difference between authentication and authorization? Give Examples

utility programs:

-Serve as tools for doing system maintenence and repairs that arent automatically handled by the operating system.

-make it easier for users to:

• copy files between storage devices
• repair damaged data files
• translate files so that different programs can read them.
• gaurd against viruses and other potential harmful programs(as described in the chapter on computer security and risks)
• compress files so they take up less disk space
• perform other important, is unexciting

- Norton provides a package that includes software tools for recovering damaged files, and repairing damaged disks.

Device Drivers:

-small programs that enable I/O devices to communicate with the computer

-included with the operating system

-Some computers store their operating system in ROM

other include only part of it in ROM

The remainder of the operating system is loaded into memory in a process called booting. which occurs when you turn on the computer.

-interacting with the operating system, like interacting with an application, cam be intuitive or challenging and it depends on something called the user interface.

User Interface

- The interface defines the look and feel of the comupting experience from a human point of view.

-MS-DOS is a disk operating system in which the user intacts using character

• letters
• numbers
• symbols

Features Included:

-Commanded-line interface

-Menu-driven interface

Graphical User Interface: Mac Os was developed by Macintosh in 1954 using GUI.

-Mulitiple User operating Sytem: UNIX and Linus

-Unix was developed at Bell labs before personal computers were available.

-linuz is free for anyone to use or improve.

Uniz remains teh dominant operating system for internet servers.

-Some of the UNIX is available for personal computers, workstations, servers, mainframes, and supercomputers.