SOFTWARE TERMS
1. What is software? What is the role of software?
Software is a detailed set of instructions that tells a computer exactly what to do, when to
do it, and how to do it. Whether it is the operating system or a word processing program,
nothing takes place in a computer without the instructions provided by one or more
software programs.
Computers are capable of performing a wide variety of tasks. The versatility of a
computer makes it unique among the tools we use. Unlike most other tools designed to do
a specific task or related set of tasks, the tasks a computer can perform are limited only
by the imagination and skill of programmers, the people who write the instructions the
computer follows. So we can define the role of software as turning a general purpose
machine, a computer, into a specific tool.
2. Name the two major divisions of software and give two examples of each type.
Software can be divided into two categories, system software and applications software.
There are three categories of system software, operating systems, drivers and utilities.
System software is all about control.
Operating systems: An operating system controls the overall operation of a computer.
An operating system is the most important piece of software on any personal computer. A
computer's operating system is responsible for almost every activity performed by the
computer. From allocating RAM to saving a file, very little that goes on inside a
computer isn't controlled by the operating system.
Drivers: In order to function, a piece of hardware installed on a computer system must
have its driver installed. Drivers are small programs that tell a computer how to operate a
particular piece of hardware. Every piece of hardware, from keyboards to modems, must
have a driver installed or it won't operate. When you buy a piece of hardware such as a
printer, it comes with a driver. Part of installing hardware involves installing its driver.
Once installed, there is no need to interact with the driver again unless it becomes
corrupted or a newer version is written by the printer's manufacturer.
Utilities: While there is little interaction between a computer operator and a driver,
utilities are primarily used by computer operators to control system hardware and files
stored on the computer. There are two places to find utilities; many come with your
computer's operating system while others are purchased by the user.
Applications: Application software is the programs we use to get things done and what
most people mean when they talk about software. Examples of application software
would be word processors, spreadsheets, fax programs or web browsers.
3. How does public domain software differ from shareware?
Public domain software is completely free. You can use it, copy it and give it away
without ever having to pay for it. The only thing you can't do with public domain
software is to sell it for a profit. Shareware is similar to public domain software in that
you can use it for free but shareware differs from public domain software in that you can
only legally use it for a limited time. Shareware is described as a try before you buy
arrangement. If you try a shareware program and don't like it, delete it from your
computer. But if you use a shareware program regularly, you are honor bound to pay the
author a registration fee, usually in the five to fifty dollar range.
4. What is an operating system? Describe the role of an operating system.
As the central control program, an operating system is the most important piece of
software on a personal computer. The role of an operating system is to control and
coordinate all components of a computer including all hardware and all other software.
Without an operating system, the most expensive collection of hardware would be
useless.
5. List the four categories of tasks carried out by an operating system.
The four categories of tasks carried out by an operating system are file, task and resource
management and providing a user interface.
File management involves functions such as saving files to disk and then saving the files
back to disk again after changes are made. A task is another name for any program
loaded into RAM. Task management involves loading files in and out of memory.
Resource management involves providing system resources to programs such as access to
the printer or coordinating the flow of signals from RAM to the CPU or to disk drives.
6. Windows 95/98 uses a hierarchical filing system to store files. What does the term
hierarchical mean with regard to a filing system?
A hard drive is like a filing cabinet. Just as a filing cabinet is divided into drawers which
are subdivided by dividers and folders, the storage space of a hard drive is also divided.
Just as the folders in a filing cabinet are arranged in an orderly fashion and contain
related information, so do the folders on a hard drive. A hierarchical filing system is one
characterized by its use of storage locations within storage locations. DOS, another
operating system for IBM and compatible computers, calls its storage locations
subdirectories while Windows 95/98 calls them folders. Regardless of what they are
called, these storage locations are used to hold related files. For example, I have a folder
called SSU on my hard drive. In that folder are folders for the two departments I teach for
here at school. One folder is called Sch of Bus and the other is called Extended Ed. In the
Bus folder I have a folder called 219 that contains files for this class. In the Extended Ed
folder I have a folder for each of the one day workshops I teach for that department. By
using this type of system, it is easy to locate files for the classes I teach.
7. Describe the role of a computer interface. Include two examples of interfaces in
your answer.
The fourth category of task carried out by an operating system involves providing an
interface for the user. The interface is the collection of components and procedures an
operator uses to give commands to or otherwise interact with the computer. The two most
common examples of interfaces used by computers today are the command line and
graphical user interface. Both the command line and the graphical user interface allow an
operator to give commands to and interact with the computer.
8. How do the two types of interfaces we discussed in class differ?
An interface can be categorized according to the options it provides a user for giving
commands to the computer. Command line and graphical user interfaces differ in how
they allow commands to be given. To give a command with a command line interface, a
user must memorize a long list of commands and then type the desired command at a
system prompt, making sure to spell it correctly. A graphical user interface (GUI,
pronounced goo-ey) is distinguished by its use of windows, icons, menus and a pointing
device, most commonly a mouse, to give commands. With a graphical user interface, it
isn't necessary to memorize a long list of commands. With a graphical user interface,
commands are selected from lists called menus. As an example of the differences
between the two types of interface, consider how you start a program. With a command
line interface, you have to learn the program's name, and type its name (often a less than
obvious abbreviation) correctly at the system prompt. With a GUI, all you have to do is
locate the program's icon and double click that icon with a mouse.
9. What is a screen prompt?
A command line interface uses a system prompt as a place on the computer screen,
identified by letters or symbols, where commands are typed. Another name for a system
prompt is a screen prompt. For example, a DOS prompt looks like this: C:\> In order to
successfully give a command, the user must memorize available commands and type
them correctly in the correct location (subdirectory). This places much responsibility on
the user. In response to user complaints regarding the difficulty involved in using a
command line interface, GUIs were developed.
10. What do the letters GUI stand for? List the four components of a GUI we
discussed in class in your answer.
The letter GUI stand for graphical user interface. A graphical user interface is
distinguished by its use of windows (a rectangular portion of the screen), icons (small
pictures that represent files or resources available on a computer), menus (a collection of
related commands) and a pointing device (usually a mouse) to give commands.
11. What is a dialog box? Include in your answer how a program uses a dialog box.
A dialog box is a special type of window used in a GUI. A dialog box is used by some
commands to present a list of options to a user or to provide a location where a user can
enter information the command needs to carry out its function. For example, a font dialog
box would present a list of the fonts installed on a computer that a user could choose
from. Or the save as dialog box provides a text box where a user can type a name for a
new file.
12. List three services an operating system provides to programs.
Services an operating system provides to programs include printing, saving, or opening a
file. Operating systems also do things such as letting you move or copy data from one file
to another or delete files you no longer want.
13. What do the letters OLE stand for? What does OLE allow you to do?
The letters OLE stand for object linking and embedding. OLE is two methods, linking
and embedding, for duplicating data in one document into other documents in the same
program or different programs. The advantage of OLE over a simple copy and paste is
that OLE provides easy access to the program used to create the data.
Linking: When you link data, you create a connection (a link) between the original data
and the copy of the data in another document. When you save changes to the original, the
link between it and the copy causes the copied data to automatically update, reflecting the
changes in the original.
Embedding: Embedding also involves copying data from one document to another.
Embedded data retain information about the program used to create it. To change an
embedded object, double click it and the program used to create the object opens,
allowing you to make changes within the program that originally created the data. Unlike
linking, embedded objects are independent of and not connected to the original. Changes
made to the original data or an embedded object have no effect on each other.
14. What is a task? What does the term multitasking mean when used with
computers?
As discussed above, one responsibility of an operating system is to control all software
programs loaded in the computer's memory. Each program loaded into a computer's
memory is called a task. A computer operating system that can manage more than one
program in memory at a time is said to be capable of multitasking. The task you are
working on is called the foreground task; all other tasks are referred to as background
tasks. For example, you start a web browser and begin to download a file over the
Internet. While the file is downloading, you start an email program. While the computer
appears to running both programs simultaneously, a computer can't actually do more than
one thing at a time. In actuality, the computer divides its processing power between the
two programs. This allocation of processing time among all running programs is called
time slicing. The computer does this so quickly that to us it appears as if all the programs
in memory are running at the same time.
15. What does it mean when someone says a file is read only? What can and can't
you do to a read only file.
A read only file is one that can be opened and read, printed or copied. However, you
cannot save changes you make to the file or delete it from the disk that holds it.
16. What does it mean to say a file is fragmented? Why can fragmented files be a
problem?
Except for the smallest of files, most files saved on a disk are not stored in one location.
Instead they are divided into pieces and stored in locations on a disk called allocation
units. Each allocation unit stores a portion of a file. The size of an allocation unit depends
on the storage capacity of the disk and may vary from 512 bytes (.5K) up to 32,768 bytes
(32K). Each file on a disk is subdivided and stored in as many allocation units as are
needed to store that file. For example, if a file is 100K, and the size of an allocation on
the disk is 32K, it would take four allocation units to hold that file. Even though the
fourth allocation unit would only contain 4K of data, the entire 32K could not be used to
hold part of another file. File fragmentation refers to a situation where the allocation units
that contain a file are not all side by side but instead are scattered over the disk. File
fragmentation can lead to two problems; fragmented files take longer to load into
memory and can be more difficult to undelete if that becomes necessary.
17. What is file compression? List two different uses for file compression.
File compression refers to a process that reduces the size of a file so that it takes up less
space on a disk. There are two uses for file compression. Using a complex algorithm, a
file compression program looks for repetitive data in a file and replaces that data with
symbols that take up less storage space than the data they represent. The end result is a
smaller file and more efficient use of the space on a disk. The second use for file
compression is to reduce the amount of time it takes to transmit a file from one computer
to another one. Smaller files take less time to transfer between computers. This is
especially important when transferring large files with modems. Files may be compressed
in one of two ways, automatically by the operating system or manually by the computer
operator.
18. What does it mean to back up a hard drive? Why is it important to back up a
hard drive regularly?
It doesn't take long for the programs and data stored on a hard drive to be worth more
than the computer itself. This is especially true if you store important or hard to
reproduce data such as original documents or financial records. A hard drive is one of the
few mechanical components in a computer. As such, it isn't a question of if your hard
drive will fail as much as a question of when it will fail. To backup a hard drive means to
make a copy of some or all of the programs and data stored on the drive to another
storage medium such as floppy or zip disks or a tape drive. While today's hard drives are
very reliable, they still do fail. Backup is important in order to protect your hard drive's
contents from accidents such as hard drive failure, accidental file deletion or theft. Ask
yourself this question, "What would happen if I didn't have access to the files stored on
my hard drive?" The more serious the consequences, the more often you need to back up
your drive.
19. What is the role of data recovery software? Why is it possible to undelete a file?
Data recovery software, generically referred to as an undelete program, is used to recover
files that have been deleted from a disk. Undelete programs work because of the way
operating systems "delete" files from a disk. When a file is deleted, its contents are not
removed from a disk. Instead, the allocation units containing the file are marked as
available for storage. Only after another file is written to those allocation units is the
deleted file gone. Undelete programs do not always work. If changes are saved to files
already on a drive or new files are added to a drive, they may overwrite the deleted files.
To increase the chances of successfully undeleting a file, stop saving files to the drive and
run an undelete program as soon as possible. The more you use your computer before
trying to undelete files, the less your chances for successfully undeleting the files.
20. What is a virus? List three things a virus might do to your computer.
A virus is a self replicating, destructive computer program. Unlike other programs, a
virus is capable of reproducing itself. Because of this, viruses can spread from one
computer to another, usually either when you open an email containing a virus or when
an infected floppy is inserted into an uninfected computer and a program is run from the
floppy. Once this happens, the virus recreates itself on the hard drive, infecting the
computer. Some things a virus might do are erase the files on a hard drive, damage
hardware or send a message (get stoned) to the user.
To protect yourself from getting a virus, install and use a virus checking program. And
remember, unlike most other programs, virus checking programs must be update
regularly! While using an old virus checking program is better than using no program at
all, because new viruses are created most every month, there may be dozens of viruses
and old virus checking program can't protect you from.