2.1.6 – Functions of an operating system

The operating system acts as an interface between the hardware and the programs.

It is the most fundamental of all system software programs.

Remember that much of the work of an operating system is hidden from the user; many necessary tasks are performed behind the scenes. In particular, managing the computer’s resources, is taken care of without the user being aware of the details.

Remember this Acronym
Short People Must Never Run Downhill
  • Peripheral Communication
  • Memory Management
  • Resource monitoring and multitasking
  • Disk access and data management
  • Networking
  • Security

2.1.7 – Outline the use of a range of application software

For the course you must be able to

  • List the proper name for the type of software
    • Spreadsheet not Excel!
    • Word Processor not Word!

List what the software does

Word Processor

A program or machine for storing, manipulating, and formatting text entered from a keyboard and providing a printout.


An electronic document in which data is arranged in the rows and columns of a grid and can be manipulated and used in calculations.

Image result for hierarchy of software

2.1.8 – Common features of applications

Many of todays software applications contain graphical user interfaces such as the well know examples below

I hasn’t always been like this. In fact GUI’s weren’t even around until the 1980’s

Before this Command Line Interfaces (CLI’s) were used.

CLI’s are still used today as although there are some disadvantages compared to the GUI, they can outperform them in other areas.


What are the common features of a GUI?

Tool bars
Dialogue boxes

More about the GUI

GUI’s can be described using the acronym WIMP (Windows, Icons, Menus, Pointers)

As most programs have GUI’s these days rather than the programmer designing all the tool bars, menus ,dialogue boxes etc he can simply state their existence and they can be displayed by the operating system saving them lots of time and effort.

This is why this looks the same across multiple programs on your computer

This not only saves time for the programmer but makes it easier  for the user as they will be familiar with the look across multiple programs and makes the learning curve for new software easier.