1.5.1 Operating Systems Flashcards
What’s the purpose of an operating system?
Provides a platform on which users can run programs
What are the two types of System Software?
Utility, Operating
State the uses of an Operating System.
User Interface & Management
Utility Programs
Device Drivers
Memory & File Management
What are the 4 types of User Interface?
Graphical User Interface
Natural Language Interface
Command Line Interface
Menu Interface
State the features of a GUI.
Windows, icons, menus, pointers
Visual & interactive
Optimised for mouse/touch gesture input
State the features of a Command Line Interface.
Text based
Less resource heavy
More commands than a GUI
More efficient
Useful for automated processes with scripts
State the features of a Natural Language Interface.
Responds to spoken language
Not always reliable (WIP)
State the features of a Menu Interface.
Successive menu presented to the user
Single option chosen at each stage
Often buttons on a keypad
What happens during Multitasking?
The processor allocates a small amount of time to each process and cycles between them
- it appears as if multiple programs are executing simultaneously due to very fast speeds
Step by step Multitasking.
Programs are loaded from secondary storage to the RAM
OS holds them in a queue
First in the queue runs its code on the processor
Program is stopped and moved to back of the queue
Next program starts running
What happens during Memory Management?
OS loads the programs in the RAM
Memory over time becomes fragmented
OS keeps track of all the parts of each program
If the memory becomes full, virtual memory is used.
How does the OS manage peripherals?
It uses Device Drivers which translate the OS instructions into a series of instructions which a specific piece of hardware can understand
Each peripheral has a Device Driver
How does the OS manage users?
Allows users to log in & access information dependant on individual user setting
- system administrator sets the user access rights for each person
