The document discusses operating systems, their functions, and examples. It explains that an operating system schedules CPU time, loads and runs applications, communicates with hardware, and provides security and file management. The document also discusses multi-user operating systems and how they allow powerful computers to be shared among multiple users simultaneously.

1. Operating Systems
YEAR 8 ICT

2. Learning outcomes
• To know the tasks that an operating system carries
out.
• To understand the reasons for needing multi-user
operating systems
• To explain the Utility programs that come with an
operating system

3. The 30 Second Challenge!
Operating System
Starter

4. In a moment some terms to do with this topic
will appear.
You will have 30 seconds to memorise them.
You will need to write down as many of
the terms as you can remember
And also a definition or explanation of how that term relates to the
topic

5. Schedules
CPU time

6. Write down as many
terms as you can
remember and write a
sentence about each
term

7. Schedules
CPU time

8. Operating systems
“Imagine you are a top computer programmer, but you live
in a world where operating systems do not exist - what would
you need to do to make the computer run your application?”
The task of looking after application software and hardware on a
computer is given over to a piece of software called the
Operating System

9. Examples of Operating Systems
• Windows for personal computers (this is
the most popular OS for home and
business users)
• Linux (Linux OS’s are open source
which means that anybody can help
develop it and it’s free, however it is more
difficult to use than Windows for most
people)

10. Examples of Operating Systems
• Mac OS X – This is the OS used by Apple
computers
• Android – This OS is used by many
smartphone manufacturers
(HTC, Samsung, Google) to operate their
phones. It was originally developed by
Google and is also open source.
• IOS – This is the OS used to operate an
iPhone and was developed by Apple. IOS
is not open source.

11. What do they do?
• Loads and runs applications -
more than one application can
run at the same time
(multitasking)
• Sends data to the correct output
devices such as monitor or
modem
• Moves data to and from hard disk
and other storage devices.

12. What does an OS do?
• Communicates with
peripherals such as printers
• It provides a ‘Human
Computer Interface' (HCI) to
allow people to use the computer
efficiently e.g. Windows interface
• Manages security such as the
use of passwords. Logging in
requires the operating system

13. What do they do?

14. Task
Complete questions 1-3 from the Operating Systems task sheet

15. Multi-User Operating System
• Most Operating systems are designed for
single users in mind but allowing for lots
of applications to be run at once (multi-
tasking)
• Most PC’s can multi-
task, however, sometimes people need a
REALLY powerful computer to do the
job.
• For example your are a scientist and
you need to run a complicated
simulation
• You are a film animator and want to
work in 3D

16. Multi – User Operating System
• Most computers can’t handle these sorts of
tasks, instead a mainframe or
supercomputer is needed!
• Supercomputers cost millions of pounds to
buy and maintain – too expensive for a single
user! This is why they have to be shared by
many users and are called Multi-user
Multi-tasking operating systems

17. Multi – User Operating System
With power equivalent to 175,000 laptops, China's
Tianhe-1A Supercomputer has been named the fastest
computer in the world, overtaking rival computers in the U.S.
and Germany.

18. Multi – User Operating System
This diagram below shows how a multi-user operating system
can manage 3 people sharing the power of one computer

19. Utility Programs
An operating system also has other built
in programs to help you to look after the
computer. These help with:
• Compressing a file to save space on
backing storage
• Recovering data from a damaged file
• Checking a disk for faults and repairing
them
• Formatting a floppy disk
• Checking the files on a disk for
computer viruses

20. Task
Complete questions 4-7 from the Operating Systems task sheet

21. Plenary
Take this quiz to test your knowledge on
Operating Systems!

22. Homework
Create a mind map about today’s lesson!