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1010 mixlplik

igpay atinlay

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Codes and ciphers have existedforhundreds of years.

People have always had theneedto hide secrets and messages.

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Caesar used ciphers and codes as didthefounding fathers of the United States.

Thomas Jeerson created ciphers andcode systems during the Americanevolution.

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Su!stitution ciphers are very commonciphers. "etters can !e reversed orrotated a certain amount.

A B C D E F G H I J K L M N O P Q ! " # $ % & ' (

' ( A B C D E F G H I J K L M N O P Q ! " # $ % &

Original Message : hello

Encoded Message : fcjjm

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A permutation can !e used to ma#e thesu!stitution cipher harder to !rea#.

A B C D E F G H I J K L M N O P Q ! " # $ % & ' (

G ' % J M N A Q ( D & $ E F " ! H # P O L C I B K

Original Message : hello

Encoded Message : qmvvt

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Su!stitution ciphers are !ro#en usingletter fre$uencies. Certain lettersoccur in the %nglish language morefre$uently than others. % occurs mostfre$uently.

A B C "

)*1+, 1*-./ /*,)/ .*0+

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Original Message : bad

Encoded Message : * * * * * *

A *

B * * *

C * *

D * *

E*

&orse code is avery

common formof cipher.

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Transpositionalciphers come in

many shapes andsi'es.

I L O $

E % O

K I N G

% I " H

C O D E

These ciphers involve storing a messagea grid and then encoding the messageusing a speci(ed pattern.

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A column ciphercould )ust run

down the columnsto ma#e a codedmessage.

I L O $

E % O

K I N G

% I " H

C O D E

Run down the columns starting with column 0.

CODED ME!"E : #E$%C&%##OOO'(D)R"*E

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A spiral ciphertypically spirals in

or out and startsat a speci(edcorner.

I L O $

E % O

K I N G

% I " H

C O D E

+rial from to+ left down and in

CODED ME!"E : #E$%CODE*"R)O&%##('O

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A pigpen cipher uses dierent shapesand dots to encode letters. The*reemasons are credited with creating

the pigpen cipher.

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"etters can !e placed in any order inthe pigpen cipher.

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A playfair cipher usesa code phrase and

a +,+ grid. -oduplicate lettersare placed in the grid.The remaining letters of the

alpha!et are used to (ll the grid.

t was used in // and //.

I L O $ E

% K N G

" H C D A

B F J M P

Q ! # $ &

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The letters to !eencoded must !e

located in the grid.

*/ is encoded to0.

S1 is encoded toU,.%A is encoded to2P.3 is encoded to

I L O $ E

% K N G

" H C D A

B F J M P

Q ! # $ &

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Use the gridto

encode pairsofletters.

I L O $ E

% K N G

" H C D A

B F J M P

Q ! # $ &

ME!"E (O CODE : %* !(

CODED ME!"E : R( (*

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The enigma machine wasused !y the -a'i regime

during /orld /ar toencode messages.

3ave eed5s%ngima

&achine

http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/http://www.dave-reed.com/DIYenigma/

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&P%26 and &P%27 (les are encoded(les.

&P%2 stands for &oving Pictures%xpert 2roup. &P%2 (les arecompressed (les.

http://www.apple.com/itunes/http://www.apple.com/itunes/

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&P6 (les are used to compress C3$uality (les. The compressionalgorithm typically compresses (les

at a 89m! to 8m!:;m! rate. A 79m! (le would compress roughly to7m!:

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=ou must have an &P%26 compati!leplayer to play an &P%26 encoded(le.

http://www.apple.com/itunes/

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