4.2 Hardware
4.2.1 Hardware components of a computer system
BBC Bitesize
BBC Bitesize covers a wide range of input and output devices. Key concepts are clearly explained. The great thing about the BiteSize site is that it links to a series of related resources, including student activities, news article links, and online dictionaries and encyclopedias.
IGCSE ICT
IGCSE ICT has notes on many topics (including input and output devices) that are useful for a range of ICT and Computing courses. The notes are very comprehensive, clearly divided into sections, well illustrated, and easily understandable for students. This is a good starting point for a lot of topics - not just for the IGCSE course.
BBC Bitesize: Data Storage
Covers all aspects of primary and secondary storage devices, including interactive lesson activities, notes, and a revision quiz. Well illustrated, this page also details the relative advantages and disadvantages of each storage medium.
IGCSE ICT: Storage
Although targetted at the IGCSE ICT syllabus, this site still has a lot of useful information for other courses. Their section on storage covers different types of storage media and storage devices, including optical, magnetic, and solid state systems. They also have a section on backing up data.
TeachICT: Storage
Teach-ICT is a popular site which covers the basic topics of computer science - in this case, with notes on secondary storage devices and comparisons in terms of capacity, speed, portability, durability, and reliability. It also has a small section on online storage (cloud computing)
Storage Devices
Edexcel GCSE Computer Science: The Processor (CPU)
Some of the details (such as static RAM) are not strictly necessary for the Edexcel syllabus, but may be useful for some students. This video explains the different types of memory (RAM, ROM, cache), the components of the CPU (including the buses), and how these relate to assembly language and machine code. A very detailed revision resource.
Lesson resources - Computer Systems
Lesson 1 - Computer Systems guides students through basic computing hardware. There are tasks to identify and describe input and output devices as well as label the internal components of the computer.
This lesson is one of the many excellent resources provided under CC-NC-SA by Mr Colley. I've added a PDF version of the original .pub documents included in the zip for those who don't have Microsoft Publisher.
Lesson resources - Storage devices
This download contains PowerPoint presentations, worksheets, and Internet resources for the topic storage devices. It includes a comparison of the types of devices and their properties.
This lesson is one of the many excellent resources provided under CC-NC-SA by Mr Colley.

Worksheet: Hardware roles
To help Computer Science students understand hardware, resource allocation, and resource management, it is helpful to have them first understand the roles each component plays in a computer system. This simple worksheet covers the key resources in a computer system, with space for examples, relevant units, and a brief description of the component's role. It is useful from early topics in GCSE Computer Courses up to the IB Computer Science HL topic Resource Management.
Spot the mistakes exercises
The slides in this presentation present basic 'facts' about computing fundamentals: input, output, binary, hexadecimal, and data representation. Each slide contains a number of basic mistakes (highlighted on the following slide). Students simply need to read through the text, spot the mistakes - and correct them. These activities work well as quick lesson starters or plenaries to check understanding.
4.2.2 Memory (RAM, ROM, cache)
4.2.3 The CPU

How Computers Work - Kinesthetic Activity
In this kinesthetic activity students act out the roles of the Arithmetic and Logic Unit (ALU), the CPU, the memory, and the display as they act out how these basic hardware components function by "running" sample programs. This is a great way of introducing the basic concepts before moving on to more advanced machine architecture. You can download the following sheets:
This activity was created by Gary Kacmarcik from cse4k12.org and is licensed under the Creative Commons CC-SA licence.

Little Man Computer (LMC)
The Little Man Computer (LMC) is a software simulator of a simple computer with a CPU, memory, and a basic instruction set. Students can enter programs in either assembly language or machine code and follow their execution by watching the change state of the program counter, accumulator, and memory. More advanced versions show animated representations of the address and data lines too. The LMC is a great tool for helping students visualise how code and data are represented in memory and how the fetch-execute cycle works.
There are now many versions of the LMC available. Some of the best include:
- Little Man Computer (Flash version) which runs in the browser
- Little Man Computer (Java applet) which runs in a web browser (Java plugin needed)
- Little Man Computer (Windows version) for Windows with .NET installed.
4.2.4 How data is stored

Magnetic, Optical, and Solid State storage
These three videos explain how data is stored on magnetic storage such as hard drives, optical storage devices such as CD-ROMS, and solid state storage such as flash disks.