Transcript 2 Operating Systems

Operating Systems
What is an operating system?
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The software that manages your
computer:
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Maintains your files
finds files
copies files
deletes files
links your printer to your application
formats disks, etc.
Some widely used operating
systems
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DOS
UNIX
MacOS
Windows
DOS
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DOS--Disk Operating System
One of the oldest PC operating systems
(Microsoft shipped first version in 1981)
Made Bill Gates a billionaire
Command line interface
UNIX
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Very large
Has many built-in programs
Used on high-end systems
Available in a smaller version called
Linux (created in 1991), available for
free
Command line interface (first version
developed at Bell Labs in 1969)
Command Line Interface
Examples
To tell the computer to copy file1into a (new)
file named file2:
 DOS
A:\> copy file1 file2
A:\>
 Unix
1> cp file1 file2
2>
Windows
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Used by most computers in the world
Graphical user interface (GUI--pronounced
‘gooey’)
This interface has been standardized across
applications by Microsoft, Inc. (version 3.0
released in 1990 as a GUI to DOS)
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This makes it easy to learn new applications since
the icons, clicking, position and types of menus
are common across applications except for
commands peculiar to an application.
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GUI (or point-and-click) designs were
developed at Xerox Palo Alto Research
Center in the late 1970’s but were never
used in commercial computer systems
at that time.
The first commercial use was in the
original Apple MacIntosh computers,
introduced in 1984.
Why a GUI rather than
commands?
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Graphical user interfaces are
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easy to learn
but perhaps slower to use because of
pointing device
Command line interfaces are
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hard to learn and easy to forget
but perhaps faster to use for experienced
user