Transcript PowerPoint - themead.org

Operating Systems
Lesson Objective:
Understanding the functions of an operating
system.
Learning Outcome:
Answer some basic questions on operating
systems.
A computer …
Memory
The computer
hardware
(e.g RAM)
Input Devices
CPU
Output Devices
(Keyboard, scanner)
(Central Processing Unit)
(Monitor, Printer)
Backing Store
(e.g Hard Disk)
The OS is the software that takes
control of the physical devices
Memory
(e.g RAM)
Input Devices
(Keyboard, scanner)
CPU
Output Devices
(Central Processing Unit)
(Monitor, Printer)
Backing Story
(e.g Hard Disk)
Memory Management
Software wants to get control of as much
RAM as possible because more RAM
usually means they run faster.
How do we stop the first item of software
grabbing all of the RAM and stopping
others from getting it?
Multi-tasking
Software wants to get as much CPU time as
possible. Sharing out CPU time between different
software is called Multi-tasking.
Peripheral management
Controlling which software gets control of
equipment attached to the computer (peripherals)
It’s good to share
Memory
Management
CPU time
(Multi-tasking)
Peripheral
Management
These are some of the tasks of
an Operating System
Also …
User Interface
How does it look? Here to put the
icons? Which language to display?
Security
Log-in, protect files from other users,
Firewall, Anti-virus …etc.
What does an Operating
System do?
An operating system is
Software
Memory Management The allocation of RAM to apps
User Interface
Multi-tasking
WIMP or other- how does it look?
Allocates CPU time to each process
Peripheral Management
Security
Printers, router, etc.
Logging in, firewall, AV