Transcript Presentation - rossparker.org

SC ICT Certification
Level 1
02 Operating Systems
By Ross Parker
02.1
INTRODUCTION
What is an Operating System
• Operating Systems (OS) bridge gulf between
hardware and applications.
Applications
Easy to use
Operating System
Hardware
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Powerful but unusable
Manage all hardware and software
Make common services available, fairly
Allow resource sharing
Allow multiple users
Command Line
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Traditional
Text only
Hard to learn
Fast for experts
Source: Wikimedia Commons
WIMP GUI
• Modern
• WIMP: window, icon, menu,
pointing device
• GUI: graphical user interface
• Easy to learn and investigate
• Slower for experts
• Came out of Xerox PARC labs
Desktop vs Server
• Desktop
– “Personal” computer
– Work performed directly on the machine
by user
– AKA “client” in client-server computing
• Server
– Shared computer
– Work performed for user “by proxy”
• Users rarely work directly on the server
The big three
• There are many OSes.
• The big three:
– Windows
– Mac OS
– Linux
• Competition is healthy
• All GUI-based
• Use all 3, be a better nerd!
02.2
WINDOWS
Windows
• Owned by Microsoft
– Actively protect their monopoly
• Developed as proprietary software.
• Largest market share (90%)
– Synonymous with desktop computing
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All started with MS-DOS
MS-DOS lead to Windows 3.1
Currently Vista is replacing XP
Shipped as OS + Applications
• Pros
Windows II
– Dominant platform
– Many applications
– Stable corporate background
– Extreme backwards compatibility
• Cons
– Slow to change and adapt
– Tries to squash competition
– Large and monolithic
– MS have all the power
02.3
MAC OS X
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Mac OS
Owned by Apple Inc.
Developed as proprietary software.
Second largest market share (8%)
Traditional stronghold in creativity
Based on Xerox work at PARC
– Popularised WIMP and “home computing”
• Currently at OS X 10.5
• Shipped as OS + Applications
• Pros
Mac OS II
– Visually appealing
– Close tie-in with Apple Mac hardware
– Great software integration
– Creativity is fun!
• Cons
– Close tie-in with Apple Mac hardware
– Apple have all the power
– Hardware is relatively expensive
– Tries to exclude the competition
02.4
LINUX
Linux
• Clone of Unix
• Started by Linus Torvalds (student) in his
Helsinki bedroom in 1991. For fun!
• Small market share (1%, only 50,000,000)
• Traditional stronghold on server side
– Making gains in desktop/laptop market
• Free/Open Source Software (FOSS)
Linux II
• Linux refers to kernel only
• “Distributions” like Ubuntu add:
– Libraries
– Installers
– Applications
– GUIs
Applications
GUI &
Libraries
• Endless variations!
– Some general
– Some specialised
Kernel
• Largest range of applications included
• Pros
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Linux III
Community driven: great spirit
Free (liberty and gratis)
Innovative, unconstrained and Rapidly evolving
Works in smallest from largest computers
• Cons
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Hard to use (in some cases)
Small user base (only 50,00,000 users)
Less stable
Nebulous
02.5
PLAYTIME!
Boring. Who cares?
Keep in mind:
1. Information controls the world
2. Computers control information
3. Who controls and restricts what you can do
with you computer?
1. Why do they do this?
2. Do you wan them to do this?
Showdown!
• Try all 3, and look to see:
– Where are the applications?
– Where are your files stored?
• Are there multiple drives or a single file system?
– How do you:
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Access the Internet?
Copy and paste?
Adjust the speaker volume?
Connect to a wireless network?
Turn the machine off
– How do you set preferences?
• Personal?
• System?
– How do they look? And feel?
– Which do you prefer and why?
Licensing
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All original work used here is licensed under the Creative Commons Attribution-Share
Alike 3.0 Unported license. For more details please look at
http://creativecommons.org/licenses/by-sa/3.0/.
This license has been chosen to permit a high degree of sharing, whilst protecting the
author’s control as to how the content is used.
Please respect this license and use accordingly!
Recycled and borrowed works from other sources are used under appropriate
licenses, which are not affected by this license. The original source is always given.
All original work created by Ross Parker (Sha Tin College, English Schools
Foundation, Hong Kong), except where specified.