Welcome to my cryptography page.  Cryptography is the science of "hidden writing" where various techniques are used to scramble a piece of information so that it can be viewed in the presence of a third party without revealing the information.

Cryptography has been around since the time of the Ancient Egyptians (1900 BC), where modified hieroglyphs were used to hide messages.   The Ancient Greeks and Romans used cryptography to send military commands and return status information using horseback messengers.   In the 20^th century, the Nazi Germans famously used a mechanical device - the Enigma Rotor Machine - to encode messages sent to and from their fleet of U-Boat submarines.

The techniques used to encode information are known as ciphers.  A cipher is basically a rule that describes how the information is encoded.  Early ciphers were quite simple and involved paper and pen and possibly a lookup table or simple arithmetic.  Later ciphers required mechanical assistance to carry out repetitive processes with the very latest requiring modern computers that can perform millions of calculations per second.

My interest in cryptography began when I started secondary school.  My school's maths department runs a cryptography club that takes part in Southampton University's National Cipher Challenge.