SC ICT Certification Level 1 02 Operating Systems By Ross Parker

INTRODUCTION 02.1

What is an Operating System Operating Systems (OS) bridge gulf between hardware and applications. Manage all hardware and software Make common services available, fairly Allow resource sharing Allow multiple users Applications Operating System Hardware Easy to use Powerful but unusable

Command Line 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!

WINDOWS 02.2

Windows Owned by Microsoft –Actively protect their monopoly Developed as proprietary software. Largest market share (90%) –Synonymous with desktop computing All started with MS-DOS MS-DOS lead to Windows 3.1 Currently Vista is replacing XP Shipped as OS + Applications

Windows II Pros –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

MAC OS X 02.3

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

Mac OS II Pros –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

LINUX 02.4

Linux Clone of Unix Started by Linus Torvalds (student) in his Helsinki bedroom in 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 Endless variations! –Some general –Some specialised Largest range of applications included Kernel GUI & Libraries Applications

Linux III Pros –Community driven: great spirit –Free (liberty and gratis) –Innovative, unconstrained and Rapidly evolving –Works in smallest from largest computers Cons –Hard to use (in some cases) –Small user base (only 50,00,000 users) –Less stable –Nebulous

PLAYTIME! 02.5

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: 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 All original work used here is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. For more details please look at 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.