In our former jobs it was vital to keep secrets, and as you know one way of doing this was esczfrs ncjaezrclasj.
Encryption of messages has been used for secret communications for over 3000 years, and it is still in use today, albeit in a much more complex form.
To make a successful cipher you need: an algorithm and a key to encrypt the information an algorithm and an identical key to decrypt the information. The key is known only to the message originator and the recipient, and must be kept secret. An algorithm is a set of steps to be followed - the instructions for using the code, similar to the method in a recipe.
There are many different ciphers, some very simple and some extremely complex.
Explore the alcoves of the Crypto-Complex to play with:
A Simple Cipher - The Caesar Cipher (a Substitution Cipher).
The Pigpen Cipher
Morse Code
The Enigma Machine
Basic Solving Techniques for Substitution Ciphers
Regardless of whether a cryptogram presents you with letters, numbers, arcane symbols, lines and dots, or wierd alien squiggles, if you are asked to replace each letter in the alphabet with another symbol, you are dealing with a simple substitution cipher.All substitution ciphers can be cracked employing the following tips:
* Scan through the cipher looking for single letter words. These are almost certainly A or I.
* Count how many times each symbol appears in the message. This is called frequency analysis, and depends on the fact that in any written language certain letters and combination of letters occur with varying frequencies. Additionally, for any one language there is a characteristic distribution of letters that remains fairly consistent for almost all samples of that language. In English the letters E, T, A and O are the most common, while Z, Q, and X are rare.
In the same way TH, ER, ON and AN are the most common pairs of letters (bigrams or digraphs) and SS, EE, TT and FF are the most common repeats
* Pencil in your guesses over the cipher. Do typical word fragments start to appear. Be prepared to erase and change your guesses.
*Look for Apostrophes. These are generally followed by S, T, D, M, LL or RE.
*Look for repeating letter patterns. These may be common letter groups, such as TH, SH, RE, CH, TR, ING and ENT.
*Try to decipher two-, three-, and four-letter words.
Two-letter words almost always have one vowel and one consonant. The five most common two-letter words are, in order of frequency, OF, TO, IN,IS and IT.
The most common three-letter words are, in order of frequency, THE, AND, FOR, WAS and HIS.
The most common four letter word is THAT. An encrypted word with the pattern 1 - - 1 is likely to be THAT. However the 1 - - 1 pattern also represents 30 other words.
*Scan for double letters. They're most likely to be LL, followed in frequency by EE, SS, OO, and TT.
Follow this link to see the above in action: