Hardware vs. Software
Computer systems consist of both hardware
and software.
Hardware refers to anything you can physically
touch.
– Keyboards, mice, monitors, and motherboards
are all hardware.
Software consists of the instructions issued to
the computer to perform specific tasks.
– The software on a computer system refers to the
programs that make the computer run.
Types of Software
Although there are literally thousands of software
programs you can buy, there are really three types
of software: application and systems.
– Application software computer software created to allow
the user to perform specific a job or task.
– Systems software is computer software responsible for
the general operation of a computer system, including the
operation of hardware, running application software, and
file management.
– Communications Software is computer software that
make it possible for a computer to transmit and receive
information to and from other computers.
Application Software
Application software is also called productivity
software.
It allows an end user to perform some task.
The most commonly used categories of
application software are
–
–
–
–
–
–
–
Word-processing programs
Spreadsheet software
Database software
Presentation software
Desktop publishing programs
Games
Graphics Software
Application Software
Most application software is defined by the
file type.
File type – an extension at the end of a file
name, indicating which application was
used to create a document
File Extensions for Microsoft Office
– .docx is Microsoft Word
– .xlsx is Microsoft Excel
– .pptx is Microsoft PowerPoint
Systems Software
Systems software consists of programs
that coordinate and control the resources
and operations of the computer itself.
The three categories of systems software
are
– Operating systems
– Utility programs
– Language translators
Systems Software – Operating
Systems
Operating systems system software that acts as
a "go-between", allowing computer hardware and
other software to communicate with each other.
There are many brands and versions of operating
systems.
An operating system is designed to work with a
specific processor chip.
– For example, Windows operating systems are
designed to work with an Intel processor (or
clone) and will not usually work on a Macintosh
computer.
Illustration of an Operating
System
This figure
shows how an
operating
system acts as
an interface
between the
user, the
application
programs, and
the computer.
Systems Software - Utilities
Utility programs are designed to help
perform housekeeping chores for the
computer.
They can be designed to
– Manage the computer’s resources.
– Do file management.
– Format disks.
– Copy files from one disk to another.
– Back up data to disk or tape.
Common Utility Programs
Disk Formatting prepares disk to have
files stored on it.
File Management is a program on a
computer that allows the user to create,
edit, view, print, rename, copy, or delete
files, folders, or an entire file system
File Recovery attempts to recover a file
that has been erased.
Common Utility Programs
Uninstall removes an application program
no longer needed.
Diagnostic provides detailed information
about the computer system and attempts
to locate problems.
File Conversion converts a file from one
format to another.
Common Utility Programs
Disk Compression frees up storage space on a
disk by compressing existing files.
Backup makes a duplicate copy of the contents
of a secondary storage device.
Antivirus protects the computer system from
viruses.
Disk Defragmentation attempts to place
segments of each file on the hard disk as close
to one another as possible.
Systems Software – Language
Translators
Computers cannot read program statements in
programming language format, such as Visual
Basic or Java program statements.
Language translator programs convert
English-like software programs into machine
code that can be understood by the computer.
Each converted English-like instruction may be
translated into many machine code instructions.
Once converted to machine code, the program
can be run and executed by the computer.
Microcomputer Operating
System Interfaces
The user interface of an operating system is
what we are all familiar with.
The User Interface is the part of the
operating system that you interact with when
using your computer.
Microcomputer Operating System
Interfaces
There are two commonly used types of
operating system interfaces:
– Command-line interface: With this interface,
you must type exact commands into the
computer from a command prompt.
This is not a user-friendly interface, and you must
memorize many commands and keywords.
– Graphical user interface: Users manipulate
on-screen icons to perform functions, usually
with a mouse or other pointing device.
User Interface Comparison
The figure on the left shows a command-line interface, where
commands are typed in at the prompt. The figure on the right is a
graphical user interface (GUI) where users perform actions by clicking
and manipulating icons.
Microcomputer Operating
Systems
If your computer is a Macintosh, you are
probably using a Mac OS.
– Macintosh computers used one of the first GUI
operating systems ever developed.
If your computer is a PC or is PC-compatible,
you are most likely using one of these operating
systems:
– DOS
– A combination of DOS and Windows
– A stand-alone version of Windows
The Mac OS
Macintosh computers were developed by
Apple Computer.
Macintosh had one of the first GUI operating
systems where icons were used to represent
programs and files.
To activate an icon, the user clicked it with the
mouse.
This was also the first operating system to
provide an on-screen help system.
The DOS Operating System
IBM introduced its first PC in 1981. Its
operating system was called DOS, which
stands for Disk Operating System.
– IBM called it PC-DOS. The operating system
was licensed from its creator, Microsoft, who
sold it under the name MS-DOS.
DOS was a command-line interface operating
system where the user had to enter commands
at a screen prompt.
It was a single-tasking operating system,
which meant that only one program at a time
could be executed.
The Windows Operating
System
Windows was Microsoft’s first GUI operating
system, released in 1987.
The first versions were called operating
environments because they acted as a shell
around the DOS operating system and worked in
combination with DOS.
Applications installed on a Windows system
appeared as icons.
– As with the Mac OS, the user activated a
Windows program by clicking the icon.
Windows Versions
The earliest versions of Windows were
labeled Windows 3.0, 3.1, etc.
The first true multitasking version of
Windows was Windows 95.
– This version also included support for
networking computers.
Multitasking is the ability to run more
than one program at a time.
Windows Versions
Windows 98 improved on Windows 95 and
offered Internet integration and support for the
USB bus.
Windows 2000 was an update to Windows 98
and Windows NT and included tools for Web site
creation.
We use Windows XP, which provides increased
stability and device recognition over earlier
Windows versions.
Windows 7 is the latest version of Windows
Operating System.
Macintosh vs. Windows User
Interface
The image on the left is an example of a Macintosh interface
window. On the right is the Windows 2000 interface.
The Unix Operating System
Unix is another early operating system that is
still widely used today.
It was developed by AT&T as part of their
phone-switching system.
It was developed to be a portable operating
system.
– That means that it was meant to run on any
hardware platform.
It is a command-line interface system,
although there are now several GUI interface
products available for Unix and Linux.
Example of a Unix System
Linux and IBM’s AIX
offer a graphical user
interface shell for a
Unix operating system,
as shown here. This
provides greater ease
of use while taking full
advantage of Unix’s
speed and reliability.
Network Operating Systems
A network operating system (NOS) is
designed to allow multiple computers to be
connected and talk to each other.
Networks are computers that are connected
to each other.
Network Operating Systems
While there are many network operating
systems available, the most popular are
– Microsoft Windows NT and Windows 2000
– Novell’s Netware
– IBM’s Warp Server
Most network operating systems makes uses
logon to use them.
– Logon is the action of gaining access to a computer
or a network by entering a username and password;
also called Login/Sign In
Communication software
Programs that make it possible for a
computer to transmit and receive information
to and from other computers.
Two Types of Communication Software
– Web Browsers
Internet Explorer, Firefox, Safari, Google Chrome
– Email
Web-based (Yahoo, Gmail, Hotmail, Live, etc.)
Email clients (Outlook, Pegasus, GroupWise, etc.)
27