Section 4:Operating system

softwareBy Alex Melhuish

Typ

ical IT

Syst

em

?Operating system software

Learning objectives

Able to explain the 6 key functions of system software

Able to explain each using a suitable example

Identify three different system software interfaces

• B the system when the computer is first switched on

• I communication with each other• O of files on the hard disk• M during multi-tasking• A between tasks• S , user and file permissions, handling

errors

Functions of an operating system(Systems Software)

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booting up the system when the computer is first switched on

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managing memory during multi-tasking

• The operating system allocates processing time and memory to the various tasks that need to be carried out.

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allocating processor time between tasks

• While computers seem to be able to multitask, a single processor can only do one thing at a time.

• Dual and quad core processors behave as if the computer has more than one processor.

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controlling where data is stored on disk

• The operating system organises the storage and retrieval of data files from backing storage such as the hard drive.

• It keeps a directory of where the files are stored on disk.

• It keeps track of the free space on the drive so that files can be stored efficiently for faster retrieval.

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communicating with input and output devices

The operating system needs to:• interface with peripherals

such as a mouse or printer• handle interrupts – signals

that need an immediate response, such as a mouse click to stop a file printing.

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system security, user/file permissions, handling errors,

Types of interface

The operating system also provides the user different interfaces, such as:

Graphical User Interface

1

2

3

https://www.youtube.com/watch?v=5AjReRMoG3Y