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Operating Systems
Lesson Objective:
Understanding the functions of an operating system.
Learning Outcome:
Answer some basic questions on operating systems.
A computer …
CPU(Central Processing Unit)
Memory(e.g RAM)
Backing Store(e.g Hard Disk)
Input Devices(Keyboard, scanner)
Output Devices(Monitor, Printer)
The computer hardware
The OS is the software that takes control of the physical devices
CPU(Central Processing Unit)
Memory(e.g RAM)
Backing Story(e.g Hard Disk)
Input Devices(Keyboard, scanner)
Output Devices(Monitor, Printer)
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 InterfaceHow does it look? Here to put the icons? Which language to display?
SecurityLog-in, protect files from other users, Firewall, Anti-virus …etc.
What does an Operating System do?
An operating system is Software
The allocation of RAM to appsMemory Management
User Interface
Multi-tasking
Peripheral Management
WIMP or other- how does it look?
Security
Allocates CPU time to each process
Printers, router, etc.
Logging in, firewall, AV