The American Cryptogram Association is an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 non-profit organization devoted to the hobby

Hobby

A hobby is a regular activity or interest that is undertaken for pleasure, typically done during one's leisure time.- Etymology :A hobby horse is a wooden or wickerwork toy made to be ridden just like a real horse...

 of cryptography

Cryptography

Cryptography is the practice and study of techniques for secure communication in the presence of third parties...

, with an emphasis on types of codes, ciphers, and cryptograms that can be solved either with pencil and paper, or with computers, but not computer-only systems.

History

The ACA was formed on September 1, 1929. Initially the primary interest was in monoalphabetic substitution ciphers (also known as "single alphabet" or "Aristocrat" puzzles), but this has since extended to dozens of different systems, such as Playfair

Playfair cipher

The Playfair cipher or Playfair square is a manual symmetric encryption technique and was the first literal digraph substitution cipher. The scheme was invented in 1854 by Charles Wheatstone, but bears the name of Lord Playfair who promoted the use of the cipher.The technique encrypts pairs of...

, autokey

Autokey cipher

An autokey cipher is a cipher which incorporates the message into the key. There are two forms of autokey cipher: key autokey and text autokey ciphers. A key-autokey cipher uses previous members of the keystream to determine the next element in the keystream...

, transposition, and Vigenère ciphers.

Since some of its members had belonged to the National Puzzlers' League

National Puzzlers' League

The National Puzzlers' League is a nonprofit organization focused on puzzling, primarily in the realm of word play and word games. Founded in 1883, it is the oldest puzzlers' organization in the world...

, some of the NPL terminology ("nom," "Krewe," etc.) is also used in the ACA.

http://www.cryptogram.org/cdb/aca.info/aca.and.you/chap08.html

Publications and activities

The association has a collection of books and articles on cryptography and related subjects in the library at Kent State University

Kent State University

Kent State University is a public research university located in Kent, Ohio, United States. The university has eight campuses around the northeast Ohio region with the main campus in Kent being the largest...

.

An annual convention takes place in August. Recent conventions have been held in Bletchley Park

Bletchley Park

Bletchley Park is an estate located in the town of Bletchley, in Buckinghamshire, England, which currently houses the National Museum of Computing...

 and Fort Lauderdale, Florida

Fort Lauderdale, Florida

Fort Lauderdale is a city in the U.S. state of Florida, on the Atlantic coast. It is the county seat of Broward County. As of the 2010 census, the city had a population of 165,521. It is a principal city of the South Florida metropolitan area, which was home to 5,564,635 people at the 2010...

.

There is also a regular journal called The Cryptogram, which first appeared in February, 1932, and has grown to a 32-page bimonthly periodical which includes articles and challenge ciphers.

Notable members

• H. O. Yardley
  Herbert Yardley
  Herbert Osborne Yardley was an American cryptologist best known for his book The American Black Chamber . The title of the book refers to the Cipher Bureau, the cryptographic organization of which Yardley was the founder and head...
  
  , who used the nom BOZO, first Vice President in 1933
• Helen Fouché Gaines
  Helen Fouché Gaines
  Helen Fouché Gaines was a member of the American Cryptogram Association and editor of the book Cryptanalysis . Her nom was PICCOLA. Shortly after the publication of the book, she died.-External links:**...
  
  , who used the nom PICCOLA, editor of the 1939 book Elementary Cryptanalysis
• Rosario Candela
  Rosario Candela
  Rosario Candela was an Italian American architect who achieved renown through his apartment building designs in New York City, primarily during the boom years of the 1920s. He is credited with defining the city's characteristic terraced setbacks and signature penthouses. Over time, Candela's...
  
  , who used the name ISKANDER, member since June 1934
• David Kahn
• James Gillogly
  James Gillogly
  James J. Gillogly is an American computer scientist and cryptographer.-Biography:Gillogly wrote a chess-playing program in the Fortran programming language in 1970, and in 1977 he ported the code for "Colossal Cave" from Fortran to C....
  
  
• Will Shortz
  Will Shortz
  Will Shortz is an American puzzle creator and editor, and currently the crossword puzzle editor for The New York Times.-Early life and education:...
  
  , New York Times Puzzle Editor

External links

• sci.crypt FAQ, part 9
• ACA Computer Supplements
• ACA list of cipher types
• "Cracking the Code of a CIA Sculpture", July 1999, Washington Post