San Antonio College Library

A look at the world of codes includes a history of how they have affected the world, from the World Wars to the death of Mary, Queen of Scots, and also looks at what the future holds for the field of cryptography.

"Codes are a part of everyday life, from the ubiquitous Universal Price Code (UPC) to postal zip codes. They need not be intended for secrecy. They generally use groups of letters (sometimes pronounceable code words) or numbers to represent other words or phrases. There is typically no mathematical rule to pair an item with its representation in code. A few more examples will serve to illustrate the range of codes"--