Teach Computing

Revision notes, activities, lesson plans, teaching ideas, and other resources for GCSE, A-Level, and IB Computer Science teachers and students.

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Examples of Local Cryptocurrencies

Digital Money for Local Communities covers three examples of country-wide c...

Hash function A hash function takes arbitrary sized input data (e.g. a fil...

Cryptocurrencies vs regular currencies

What is Bitcoin and How Does it Work? is a high level overview of the Bitco...

Examples of Cryptocurrencies

Bitcoin is by far the most well known cryptocurrency. The Bitcoin website w...

Practice paper 3 exam questions

One of the drawbacks of the yearly case study is that there are no past p...

Emergency Management System Explainer Video

This short video gives an overview of some EMIS features. It includes many ...

Geographic Information Systems (GIS)

For some functionality, an EMIS may also be connected to a GIS (Geographic ...

Programming languages - from Scratch to machine code

The CS Field Guide has a very comprehensive guide to different types of pro...

Assembly language simulators

There are several assembly language simulators available for use online. Si...

Resources discount offer

1.2 Communication and Internet technologies

Click here for recommended Cambridge A-Level Computer Science textbooks.

1.2.1 Networks

Connecting to the internet diagram

Connecting to the Internet

The BBC's Connecting to the Internet does a good job of explaining the requirements for connecting to the Internet as well as the major media types (including, copper cable, fibre optic, ADSL, and 3/4G). The pages are very detailed and give advantages and disadvantages for each connection type.

Updated: 2016-03-27
Internet backbone map

Greg's Cable Map

Greg's Cable Map is an excellent site with an interactive map showing the location of major Internet backbones across the world. This is a great resource for helping students visualise just how Internet routing works.

Updated: 2016-03-27


BBC Bitesize has a good overview of the differences between LANs and WANs, including some very clear diagrams. It does not cover Personal Area Networks (PAN) though. The very similar GCSE Computer Science page includes both a video and an explanation of WPAN and PAN.

Updated: 2016-04-05
Cable types

Network cable types

About Tech has one of the better explanations of network cable types, covering the essentials including coaxial, twisted pair, and fibre optic. The hyperlink-studded text makes it easy to students to find out about any related terms or concepts which confuse them.

Updated: 2016-04-05
Fibre optic cables

How undersea cables are laid

This short video makes a good lesson starter or discussion prompt. It shows how fibre optic cables used for Internet backbones are laid beneath oceans. This is really useful for showing students that Internet routing is not a complicated or mythical process but, in fact, one which uses relatively basic technology.

Updated: 2016-04-05
How the Internet works

A Guide to How the Internet Works

This smart-looking Prezi presentation by Phil Bagge is packed full of great graphics and makes a really use introduction to the Internet topic. It takes a clear and visual approach to the idea of a 'network of networks', and really helps students see the structure of the Internet.

Updated: 2016-04-05

1.2.2 IP addressing

Internet protocols

What Happens When You Click a Link?

This video explains step by step what happens when you enter a URL in your web browser. It covers looking up the IP address using the HOSTS file or DNS, connecting to the destination machine using TCP/IP, and using HTTP to fetch the page. It does a good job of breaking down the process into a series of simple steps that demystify this process for students (hopefully!).

Updated: 2015-05-02
Internet Routing

IP addressing and routing

The final part of this BBC Computer Science page deals with issues of IP addressing and routing.

Updated: 2016-03-27

1.2.3 Client- and server-side scripting