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− | Cryptography is the process of hiding messages; either by concealing them (eg. hiding them in an image), or by obfuscating them outright (eg. substitution cipher).
| + | To learn about cryptography, check out the [http://gamedetectives.net/academy Game Detectives Academy] - a free, interactive series of tutorials! |
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− | == Basic Terminology ==
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− | * '''Cipher''': a method of encryption
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− | * '''Plaintext''': the legible text of a hidden message
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− | * '''Ciphertext''': the text after a message is concealed in it
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− | * '''Encryption''': The process of turning plaintext into ciphertext
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− | * '''Decryption''': The process of converting ciphertext back into plaintext
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− | * '''Key''': a string used by the cipher that is neither the plaintext nor the ciphertext
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− | == Basic Ciphers ==
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− | === Caesar cipher ===
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− | The simplest example of a cipher is the Caesar cipher. The rules of the cipher are as follows:
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− | Let '''n''' equal a value from 1 to 25
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− | Shift each letter in the plaintext forward by '''n''' positions in the alphabet
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− | The resultant string is the ciphertext
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− | For example, to encrypt the string <code>Game Detectives</code> using the Caesar cipher, using an arbitrary '''n''' value of 2, then:
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− | G -> H -> I
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− | a -> b -> c
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− | m -> n -> o
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− | e -> f -> g
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− | ...
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− | and the resultant ciphertext would be <code>Icog Fgvgevkxgu</code>. To decrypt this string back into <code>Game Detectives</code>, the process can simply be reversed by shifting each letter of the ciphertext 2 places backwards.
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Latest revision as of 14:37, 24 May 2018