As you enter each section of the Black Chamber, you typically encounter a new code. Each page will contain an explanation of how the code works, some history that puts the code in context, and an interactive tool that will allow you to encrypt and decrypt messages.

The interactive tools allow you to type in a message and you can often encrypt it letter by letter or with a single mouse click. You can print the encrypted message or you can cut and paste it into an email and send it to a friend, who can decode the message by visiting the website. You could even 'text' the coded message via your phone.

In order to decode the message, your friend will usually need the 'key' that you used to encrypt the message, which is typically a list of letters or a secret word, but all of this is explained on the relevant page for that code. You will also discover hints, tips and tools that will help you crack intercepted messages.

You can skip from page to page by clicking on the Next Page button, which will effectively present you with a mini cryptography tutorial. Or you can jump to particular pages by examining the contents page.

If you have fully explored the Black Chamber and still want to know more, then you can explore the CD-ROM, or you can visit Crypto Corner, also part of Simon Singh's website, which includes features, articles, links and book recommendations.

Please note, this site has not been designed for printing, but for interactivity. However, you can print pages using the following routes:

1.	On your mouse, right click and choose Select All, then copy and paste into a word document. Or:
2.	Press the Print Screen button on your keyboard and paste into a word document. Or:
3.	Select Print from Explorer, but first go into Tools, then Internet Options, then Advanced, and switch off "Print background colours and images".