What is an OS?
- An operating system (OS) is a fundamental software that manages the computer hardware, provides common services for computer programs, and acts as an interface between users and the machine
- There are several different types of operating systems, each with unique characteristics and purposes
- Understanding these types is essential for both developing and using computer systems
What are the different types of operating systems?
| Type | Description |
|---|---|
| Distributed Operating Systems | Run on multiple machines appearing as a single unit, used for efficient task distribution and load balancing |
| Embedded Operating Systems | Designed for specific tasks, is the system running inside a device that is not primarily a computer system, e.g. microwave, dishwasher, washing machine |
| Multi-tasking Operating Systems | Allows multiple tasks to run concurrently on a single processor, manages system resources and allocates CPU time to different processes |
| Multi-user Operating Systems | Supports multiple users accessing computer resources concurrently, efficiently manages resource allocation, and provides features for data security and user privacy |
| Real-Time Operating Systems (RTOS) | Designed for immediate data processing, and can ensure tasks are processed in specific timeframes, highly efficient |
Examples
| Type | Example |
|---|---|
| Distributed Operating Systems | Hadoop is an open-source OS designed to process big data using multiple nodes in a distributed network. |
| Embedded Operating Systems | IoT devices and many household devices contain embedded OS. These devices don’t typically run a well-known OS. They run a proprietary OS that has a simple set of functions. |
| Multi-Tasking Operating Systems | Windows, MacOS, and Linux are multi-tasking OS that can run multiple applications simultaneously. |
| Multi-User Operating Systems | Windows, MacOS, and Linux are multi-user OSs where multiple users can log in and run independent processes. |
| Real-Time Operating Systems | Real-time OS are used in industries like aerospace and automotive where low latency is critical to safety. |
Worked Example
A taxi firm is investigating replacing its drivers with self-driving cars.
Explain why the self-driving system will use a real-time operating system.
[3]
How to answer this question:
- Be able to state the purpose of an operating system and recall the advantages of a real-time operating system
- Link the advantage to the scenario in the question
Answer:
Example answer that gets full marks: A self-driving car system must process data in real-time from input sensors such as radar cameras. Data needs to be processed instantly so that the vehicle can operate safely. A vehicle that cannot process data quickly will be an unreliable danger to people. Faster processing of input data will lead to safer operation of the vehicle. A real-time system will replicate hazard perception, navigation, and vehicle control that humans can instinctively do.
Acceptable answers you could have given instead:
An operating system needs to process tasks quickly. A real-time operating system needs to process them instantly. A real-time operating system should be used in a self-driving car so that it can react to hazards quickly.
Worked Example
A company releases an in-home virtual assistant called ‘Bertie Butler’. When placed in a room, the device listens out for the phrase “Hey Bertie”. When someone says that phrase, it listens to the following question and tries to give a relevant answer.
The Bertie Butler device runs off an embedded operating system.
Define the term ‘embedded operating system’.
[2]
How to answer this question:
- Recall the features of an embedded system
- Use the scenario to include examples in your answer
Answer:
Example answer that gets full marks: Embedded systems are those running inside everyday items that are not primarily computers. Embedded systems usually have a simple set of features that they perform efficiently. Some other embedded systems, such as microwaves, have much simpler features and functions.
Acceptable answers you could have given instead:
An embedded system runs in most household devices that require some processing e.g. microwaves, dishwashers, electric toothbrushes