1.5 System Software

What is the purpose and functionality of an operating system?

Provide a platform on which users can run programs.

Manages the hardware and software resources in a computer system.

Operating system software falls under system software. The other type is utility software.

What are user interfaces?

How a user interacts with a computer/ hardware

It outputs data to the user, receives input from the user.

What are the types of user interfaces?

Command line interface

Graphical user interface

Natural Language Interface

Menu interface

What is command line interface?

User interface that is text based and the user writes commands.

Less resource heavy compared to a GUI

For advanced users

Efficient

More commands than a GUI

Automate processes using scripts

What is a Graphical User Interface (GUI)?

User interface that contains windows, icons, menus and pointers (WIMP)

Visual

interactive optimised for mouse and touch gestures

Intuitive

Everyday use

What is natural language interface?

User interface that uses voice to interact with the computer/hardware

Not reliable

Responds to questions in spoken language

What is menu driven interface?

User interface that has a series of limited menus shown to the user.

Often Buttons on keypad

Single option chosen at each stage

What is multitasking?

Allows multiple programs to be open and running at the same time

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Programs are loaded from secondary storage into RAM.

The operating system holds these programs in a queue. The program at the front runs its code on the processor.

After a short time, the program stops running and is moved to the back of the queue.

The next program in the queue then starts running.

The cycle continues

What is memory management

Moves data from secondary storage to RAM

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The OS also splits programs/data efficiently in memory by fragmenting them to maximise the use of space.

What is fragmentation?

Splitting a program or file into pages so that it can placed in free spaces in memory/secondary storage.

What is peripheral management?

How the operating system communicates with the hardware

What are device drivers?

Software/ program that allows the operating system to communicate with the peripheral

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translate instructions so the hardware understands

What is user management?

Allows multiple users to login into a computer and retain individual settings for each user.

Different users may have different access levels to certain files

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OS can be single user or multi user

A multi user OS allows multiple accounts in one device.

What is file management?

The organisation of the data into a manageable hierarchal structure. It allows the user to create, delete, copy, rename and move files

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It also reads/ write the data to the hard drive and keeps track of the sectors it is written to.

File extension let the OS know what application they need to use to open e.g. jpeg - images, mpeg - video, docx - document, xls - spreadsheet