Cryptography

The book I read to research this post was Cryptography for Dummies by Chey Cobb which is an excellent book which I bought from amazon. The ancient greeks & romans developed which were things like wrapping a long piece of paper around a stick of a certain thickness writing vertically to be read on an identical stick or using a code that was merely advanced say 8 characters & might involve a ring with 2 lots of letters one of which rotated. In them days they got away with codes like that because most people were illiterate. In the first & second world wars codes & their use advanced in a huge way. It's interesting to note that nowadays most cryptography is in use by the public & by companies because their has been a lot of concern about the safety of peoples passwords in things like credit cards user accounts on the internet. Also the use of cryptography is on the increase for the same reason. Governments have whole departments devoted to making and breaking codes although they are often at least partly based on commercially used ones. Also when a new encryption method comes out there are loads who try & find a weakness in it. One method called DES was deemed too easy to break so they brought out 3DES where DES is performed 3 times the number of permutations is huge & contrary to what you see in films often the only way to break a cipher is brute force or cycling through the possible where you are looking at several hours at least. Often the tools for breaking ciphers are freely available as freeware or shareware on the internet. Something of concern is wireless networks where passwords can often be broken in a few hours & literally thousands of companies have freeloaders piggybacking on there networks going on the internet.