Algorithms used earlier in the history of cryptography are substantially different from modern methods, and modern ciphers can be classified according to how they operate and whether they use one or two keys.

Even though the goal has been the same, the methods and techniques of cryptanalysis have changed drastically through the history of cryptography, adapting to increasing cryptographic complexity, ranging from the pen-and-paper methods of the past, through machines like Bombes and Colossus computers at Bletchley Park in World War II, to the mathematically advanced computerized schemes of the present.

Stephenson explores subjects such as mathematics, cryptography, philosophy, currency, and the history of science.

During the early history of cryptography, two parties would rely upon a key using a secure, but non-cryptographic, method.

In the history of cryptography, Typex ( alternatively, Type X or TypeX ) machines were British cipher machines used from 1937.

In the history of cryptography, 97-shiki ōbun inji-ki ( 九七式欧文印字機 ) (" System 97 Printing Machine for European Characters ") or Angōki Taipu-B ( 暗号機 タイプB ) (" Type B Cipher Machine "), codenamed Purple by the United States, was a diplomatic cryptographic machine used by the Japanese Foreign Office just before and during World War II.

The history of cryptography provides evidence that it can be difficult to keep the details of a widely used algorithm secret ( see security through obscurity ).

In the history of cryptography, the ECM Mark II was a cipher machine used by the United States for message encryption from World War II until the 1950s.

The history of cryptography begins thousands of years ago and contains a variety of different types of encryption.

Financial cryptography is distinguished from traditional cryptography in that for most of recorded history, cryptography has been used almost entirely for military and diplomatic purposes.

His written works include Fermat's Last Theorem ( in the United States titled Fermat's Enigma: The Epic Quest to Solve the World's Greatest Mathematical Problem ), The Code Book ( about cryptography and its history ), Big Bang ( about the Big Bang theory and the origins of the universe ) and Trick or Treatment?

As well as explaining the science of codes and describing the impact of cryptography on history, the book also contends that cryptography is more important today than ever before.

* Kahn, David – The Codebreakers ( ISBN 0-684-83130-9 ) A single-volume source for cryptographic history, at least for events up to the mid -' 60s ( i. e., to just before DES and the public release of asymmetric key cryptography ).

Kahn has written other books and articles on cryptography, and on cryptographic history.

* Singh, Simon, The Code Book ( ISBN 1-85702-889-9 ): an anecdotal introduction to the history of cryptography.

It is both a history of cryptography, and a discussion of mathematical topics related to cryptography.

* Budiansky, Stephen, Battle of Wits: a one-volume history of cryptography in WW II.

The Codebreakers – The Story of Secret Writing ( ISBN 0-684-83130-9 ) is a book by David Kahn, published in 1967 comprehensively chronicling the history of cryptography from ancient Egypt to the time of its writing.

It is widely regarded as the best account of the history of cryptography up to its publication.

The book was republished in 1996, and this new edition includes an additional chapter briefly covering the events since the original publication ; see the " Books on cryptography " article for other works which cover this later history in more detail.

So, for happy years, Helva scooted around in her shell with her classmates, playing such games as Stall, Power-Seek, studying her lessons in trajectory, propulsion techniques, computation, logistics, mental hygiene, basic alien psychology, philology, space history, law, traffic, codes: all the et ceteras that eventually became compounded into a reasoning, logical, informed citizen.

Hammurabi is known for the set of laws called Hammurabi's Code, one of the first written codes of law in recorded history.

Mesopotamia, as shown by successive law codes, those of Urukagina, Lipit Ishtar and Hammurabi, across its history became more and more a patriarchal society, one in which the men were far more powerful than the women.

The codes of Justinian, particularly the Corpus juris civilis ( 529-534 ) continued to be the basis of legal practice in the Empire throughout its so-called Byzantine history.

United States ' direct participation in World War II commenced in 1941 with Lend-Lease and the Attack on Pearl Harbor, but the history of capturing Enigma machines and breaking their codes had already begun in Europe.

In the past, when there was no writing, the Lhobas kept track of history through telling their descendants and tying knot codes about their past.

In May 1996, Bath Rugby and Wigan RLFC made history by playing against each other at both codes.

Where the history of these legal codes has been traced, there is also a record of the change in the definition of the elements constituting sedition at certain points in history.

These traditions are a form of oral history for the Ghegs, and also " preserve and inculcate moral codes and social values ", necessary in a society that, until the early 20th century, relied on blood feuds as its " primary means of law enforcement ".

Pashtuns embrace an ancient traditional, spiritual, and communal identity tied to a set of moral codes and rules of behaviour, as well as to a record of history spanning some seventeen hundred years.

In 1997, he began working on his second book, The Code Book, a history of codes and codebreaking.

Historical manuscripts such as the 6th century Codex Purpureus Beratinus, discovered in 1868, and the Codex Aureus, a 9th century Greek language manuscript have revealed much about the history of the region and that Berat had a reputation for producing manuscripts ; 76 of the 100 codes protected in the National Archives of Albania are from Berat, indicating its historical importance.

* American history, an abbreviation used in university course codes

" In fact, Sorel makes no justification of violence by philosophical argument, but uses long excursions into history and current events to demonstrate that ethical codes are relative to their time and place.

Although he is no longer the leading points scorer in Test history, he is still considered to be one of the most accomplished goalkickers in both rugby codes.

She studied rape throughout history, from the earliest codes of human law up into modern times.

Kingaroy has a rich history with Australia's four Football codes.

The Research Tower is no longer in use because of the change in fire safety codes, although the company is committed to preserving the tower as a symbol of its history.

* The Doctor disarming the missiles here plays a crucial role in the Virgin New Adventures novel Return of the Living Dad, when a group led by the father of the Seventh Doctor's companion Bernice Summerfield attempt to force the Doctor to give them the missile codes he used here as part of a plan to change history.

Van Seters attempts just such a reevaluation of legal history among the biblical codes in A Law Book for the Diaspora: Revision in the Study of the Covenant Code ( 2003 ).

In 1962 he became the only player in history to play in two provincial Railway Cup finals, in hurling and football, on the same day, winning medals in both codes for Leinster.

His brochures covered football of both codes ( he edited the " Playfair Rugby Annual " for many years ) and his books included one on the University Boat Race, as well as a short history of cricket and other histories of Surrey CCC, such as " The Surrey Story ", West Indian cricket and the Gillette Cup ".