iGCSE Computer Science - Distance Learning

Tutor Marked Assignment 6
Tutor Marked Assignment 8 (Programming)

The Role of Operating Systems

Operating systems are a type of system software that is vital in order for our computer systems to actually run. All computer systems will have some form of operating system in order to:

  • Manage the computers  hardware and peripheral devices
  • Provide an interface to the user
  • Manage software
  • Manage memory
  • Manage users

Providing An Interface

Operating System

The interface provides a user-friendly screen instead of showing the complexity of the operating system code. The majority of operating systems that we come across in everyday life will be graphical user interfaces (GUI). These can be easily identified by their for distinguishing features: windows, icons, menus, and pointers, or WIMP for short.

GUIs are installed with operating systems as they are easier for non-technical users to use with very little training. However, these are not the only interfaces that an OS may have.

Command-line interfaces (CLI) allow highly technical users to access all areas of the operating system through a set of written commands and no images. Whilst these are much quicker and allow greater access, they are also much more prone to issues for non-technical users and much more difficult to use.

Lesson Task

Create an infographic poster showing the different types of interface available for software (include GUI vs. command line). Don’t forget to include images showing what each interface looks like, who they are designed for, and how they are similar. You may wish to use software like Canva for this task.

Managing Hardware

Internal Hardware

The operating system manages hardware through additional “bolt-on” software called a driver. A driver is a small piece of software that tells the operating system what the peripheral does, and how to obtain data from it and send databack.

For example, when you plug in a new mouse you will often see a pop-up that tells you that your operating system is searching online for a driver before it can install your new piece of hardware. Once downloaded and installed, the driver extends your operating system allowing it to detect the movement of the mouse and output this as a pointer on your screen.

Lesson Task

Investigate why different operating systems need different drivers for the same piece of hardware. Use one of your peripheral devices such as your mouse or keyboard as an example. You may wish to refer back to the Embedded Systems page to help you with this task.

Managing Software

Managing software includes the storage of software, its data, and also how the software interacts with the hardware on the system. The operating system also acts as a platform on which to install an additional piece of software. This means that you cannot install any software onto your computer system until it has an operating system.

Managing Memory


As the operating system is key to managing the hardware of the computer systems, part of that is allocating primary memory for data and programs.

As new programs are started, the operating system helps to allocate space in the RAM to hold the required programs and data, and smaller sections of primary memory within the cache to hold the instructions that allow us to interact with the hardware & software of our computer systems.

Lesson Task

Create a diagram showing how the operating system may allocate memory in the RAM whilst programs are running. You may wish to extend this to show how this is used as part of the Fetch Decode Execute cycle.

Managing Users


Most operating systems will allow more than one user account (although they log in at different times). When a user account is created a folder structure is assigned to hold their personal files, keeping them hidden from other users.

Often, there will be different levels of user accounts including administrators that have access to all areas, and individual users access is limited to just their own files.

Revision Task

Download and complete the visual notes below. Don’t forget to add colour to the keywords and add your own notes in the areas provided.