Operating Systems &
Applications Software
Lesson 8
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What is an Operating System?
How many bytes is one megabyte?
gigabyte?
How would you calculate the number
of bits in 8 Kbytes? How many are
there?
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Define software, OS software, and
applications software.
Understand the history purpose of
OS software.
Identify and categorize different
types of software.
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Coordinates and controls all basic
operations on the computer
Interface between the hardware and
the software (some through the BIOS)
Manages the processing of
application programs
Transfers data to/from disks
Handles all printer and keyboard
functions
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A computer with no software loaded
can do absolute nothing
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Users rarely communicate directly
with the computer hardware
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Programmers deal with the hardware
through the Operating System
Without
an OS users would have to know all
of the technical commands/codes required to
control and operate the equipment connected
to the computer system
All
programs must first go through the OS in
order to access the hardware
OS
may use the BIOS to interface with the
hardware
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Apple Mac OS/X
Linux
Unix
Windows XP, Vista, 7
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1980: MS-DOS
1982: Windows 1.0
1987 – 1992: Windows 2.0 – 2.11
1990 – 1994: Windows 3.0, NT
1995 – 2001: Windows 95
1998 – 2000: Windows 98, 2000, Me
2001 – 2005: Windows XP
2006 – 2008: Windows Vista
2009 – Present: Windows 7
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History Timeline
Graphical User Interface (GUI)
 Common User Access (CUA)
 Clipboard: Cut/Copy/Paste
 Multi-tasking or task switching
 Run several programs or perform
multiple tasks simultaneously
 Object Linking and Embedding (OLE)
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Examples: Cell phones & Smart Phones
Computer in a typical modern cell phone is
now more powerful than a desktop computer
from 20 years ago
Operating systems are made out of portable
code rather than permanent physical circuits
is so that they can be changed or modified
without having to scrap the whole device
Remember the ENIAC?
Programs
that allow you to make the
computer do what you want
Write a letter, browse the Internet, draw a
picture, etc.
Depends on the operating system
Applications that run on one operating system
(Windows) cannot run on a different operating
system (Unix or MacOS) unless they are rewritten
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Word Processors – MS Word, Google Docs
Spreadsheets – MS Excel, Google Spreadsheets
Presentations – MS PowerPoint, Google
Presentation
Databases – MS Access
Communications – MS Outlook
Accounting – Peachtree, QuickBooks
Animation/Gaming – Alice, Gamemaker