ciphers and hidden messages

-Ciphers !!!!! what's the ciphers ? and in what they help us ? what's the use of them ?

a cipher (or cypher) is an algorithm for performing encryption or decryption , a series of well-defined steps that can be followed as a procedure , An alternative, less common term is encipherment.To encipher or encode is to convert information into cipher or code. In common parlance, 'cipher' is synonymous with CODE, as they are both a set of steps that encrypt a message; however, the concepts are distinct in cryptography, especially CLASSICAL CRYPTOGRAPHY. 

-How could we decipher a cipher !!!!

it depends on what a cipher we wanna decipher and which kind of idden messages you got, in the entire world there's a lot of codes that can be use as cipher and there many ways how to sent a hidden message and there's no way to find out the right way to decipher it, At least now !!

   so first off let's figure the kind of ciphers out .

- The "caesar cipher" :

also known as CAESAR's SHIFT or CAESAR's CODE, is one of the simplest and most widely known encryption techniques, it is a type of "substitution cipher" in which each letter in the plaintext (is information a sender wishes to transmit to a receiver) is replaced by letter some fixed number of positions down the alphabet .

i'll an example, with a left shift of 3, D would be replaced by A, E would became B, and so on .The method is named after "julius caesar"( it's a long story about him i'll tell it later ), who used it in his private correspndence .

this is the wheel of caesar to make the code more easy.

- you can arrange with your friend the best way to use this cipher and send hidden messages ;)

 - The "Vigenére cipher" :

this is one of the most  three complicated ciphers, it needs a high abilities of observation it took me two days to find out the way it works, so let's explain it .

THE Vigenére Cipher is a methode of uncrypting alphabetic, text by using a series of diffrent caesar cipher based on the letter of a keyword, it's a simple form of polyalphabetic substitution .

In a caesar cipher, each letter of the alphabet is shifted along some numbers of places, for example in a caesar cipher of shift 3, A would become D , B would become E and Y would become B and so on . The vigenére cipher consists of several caesar cipher in sequence with diffrent shift value .

To encrypt, a table of alphabets can be used, termed a "tabula recta" or "vigenére square" it consists of alphabet written out 26 times in diffrent rows, each alphabet shifted cyclically to the left compared to the previous alphabet from one of the rows, the alphabet used at each point depends on a repeating keyword.

For example, suppose that the plaintext to be encrypted is :

ATTACKATDAWN

the person sending the message chooses a keyword and repeats it until it matches the length of plaintext, for examle the keyword is lemon :

ATTACKATDAWN

LEMONLEMONLE

then use the table in below :

for example, the first letter of plaintext is A, is paired with L, the first letter of the key, so use row L and column A of the table. Namely L, similarly, for the second letter of the plaintext, the second letter of the key is used, the letter at row E and column T is X . The rest of the plaintext is enciphered in a similar fashion :

Plaintext:	ATTACKATDAWN
Key:	LEMONLEMONLE
Ciphertext:	LXFOPVEFRNHR

so this is the easest way the decipher it, and by the time it will turn easy .

- some ciphers :

there's a lot of codes and ciphers to learn like " the pig pen code" and "the transposition cipher" and "morse cipher" .

so if you learn it well you can solve some cryptograms in this web site :

http://www.cryptogram.org/resources/solve-a-cipher/