Cryptography
Cryptography is the writing of secrets. The word 'cryptography' comes from the Greek 'cryptos', secret, and 'graphos', writing.
Examples Of Cryptography
Cryptography is probably as old as mankind (only about 6000 years). From the very beginnning of time, people have needed to keep secrets from one another. Generally, 'cryptography' refers to encoding, which is the process of taking plain text (like this) and making it difficult (or impossible) to understand.
One of the oldest and easiest cyphers (a pair of keys used for encryption and decryption) is the substitution cypher. To use this cypher, simply write out the alphebet and then write the numbers from 1 to 26 under each letter, so that A = 1, B = 2, C = 3, etc. Thus, 'Conservapedia' becomes '3 15 14 19 5 22 1 16 5 4 9 1'. Another easy substitution cypher is to write out the alphabet from A to Z and then write the alphabet again underneath, this time from Z to A. In this cypher, A = Z, B = Y, C = X, and so on. Using this cypher, 'Conservapedia' becomes 'x l m h v i e z k v w r z'.
To make things a little more difficult for anyone that intercepts the message, one can string the numbers or letters together in one solid lump. For example, here we have the sentence 'The quick brown fox jumps over the lazy dog'. In a simple numerical substitution cypher (with slashes to separate words), it looks like this:
20 8 5 / 17 21 9 3 11 / 2 17 15 24 14 / 6 15 24 / 10 21 13 16 19 / 15 22 5 18 / 20 8 5 / 12 1 26 25 / 4 15 7
Now, if we remove the slashes and spaces, we get this:
2085172193112171524146152410211316191522518208512126254157
It still says the same thing, but it's far more difficult to decipher. To make it even more difficult to decipher, we can put spaces back into the string of numbers -- at random, like so:
20851 721 931121 7152 4146 152 410211 31619 15 2251 820851 212 625 4157.
This is a fairly strong cipher, provided that you're only working with a pencil and a piece of paper. With the advent of computers, this sort of encryption is little better than writing your message on a paper napkin and folding it in half.
Computer programs can easily break this cypher using "brute force". The encrypted information is input into the program, which is then set into motion. The program tries every combination of letters, dumping the results into a file. The file is then reviewed by the person that put the information into the program (this person is usually a criminal, known as a "hacker").
Historical Uses Of Cryptography
Generally speaking, cryptography has been the sole domain of governments, which is as it should be. All governments of the world have a branch dedicated to the interception and decryption of encoded information. In America, this is the CIA; in Britain, it's MI5; in Vatican City it's Iscariot (Vatican Section XIII).
Cryptography has played a large part in many wars. In the first world war, Mata Hari was responsible for carrying messages back and forth for the German government, causing the deaths of thousands of French soldiers. In the second world war, British soldiers captured the crew and The Enigma Engine of German U-boat U-571, leading to the decryption of Nazi communications and the end of the war.
Other examples of the importance of cryptography include Ethel and Julius Rosenberg.
Ethel and Julius Rosenberg sold US atomic secrets to the USSR at the height of the cold war. They were convicted and executed at Sing Sing prison.
As you can see, cryptography leads to nothing more than trials and death. It's not something that the average person should get involved with.{[fact}}