Most Common Cyphers
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Most Common Cyphers
The A1Z26 code is a very simple code. As you know, there are 26 letters in the American alphabet so Z would equal 26 because it is the 26th letter in the alphabet.
A=1 B=2 C=3 D=4 E=5 F=6 G=7 H=8 I=9 J=10 K=11 L=12 M=13 N=14
O=15 P=16 Q=17 R=18 S=19 T=20 U=21 V=22 W=23 X=24 Y=25 Z=26 0=SPACE
20 8 9 19 0 9 19 0 5 1 19 2
this is easy
An anagram is word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
Rearranges to: Silent
ASCII is a computer code that is similar to binary. Instead of using 1's and 0's like binary it uses the numbers from 1-256.
A=65 B=66 C=67 D=68 E=69 F=70 G=71 H=72 I=73 J=74 K=75 L=76
M=77 N=78 O=79 P=80 Q=81 R=82 S=83 T=84 U=85 V=86 W=87 X=88
a=97 b=98 c=99 d=100 e=101 f=102 g=103 h=104 I=105 j=106 k=107 l=108
m=109 n=110 o=111 p=112 q=113 r=114 s=115 t=116 u=117 v=118 w=119 x=120
SPACE=32 !=33 "=34 '=39 (=40 )=41 , (comma)=44 .(period)=46 /=47 ?=63
116 104 105 115 32 105 115 32 101 97 115 121
this is easy
The Abtash code is just the alphabet backwards. For example, A would equal Z.
A=Z B=Y C=X D=W E=V F=U G=T H=S I=R J=Q K=P L=O M=N N=M
O=L P=K Q=J R=I S=H T=G U=F V=E W=D X=C Y=B Z=A
gsrh rh vzhb
this is easy
The acrostic cypher breaks the word(s) you want to send down into individual letters. These letters are then inserted into a larger body of text with each of those letters being the beginning of a new phrase of the acrostic code. The reader can then see that the beginning letter of each sentence put together spells a word(s) that was the original message.
L - Looks like a simple paragraph.
O - Only you have encoded a message here.
V - Very easy to do.
E - Especially useful in battle.
Y - You don't need a key to solve.
O - Only your own mind and eyes.
U - Unless you have
There are other versions of this cypher. When encrypting the letters in the middle of the line it is called a mesostic acrostic cypher. When encrypting the letters at the end of a line it is called a telestic acrostic cypher. When using letters at the beginning and end of every line it is called an acroleuton acrostic cypher.
A Bifid cypher combines a Polybius Square cypher with a Transposition cypher and was invented by Felix Delastelle, who also invented the trifid and four square cyphers. The key for the bifid uses a 25 letter 'key square' much like the polybius square that usually omits the letter "J" or combines it with the letter "I".
When encrypting write your message out across the page. Next look up each letter and write the row number under each letter. Then under the row number write the column number in a fraction form like below. Our plaintext message is: DEFEND THE EAST WALL
Next write the numbers in a line starting with the top line then continuing to the bottom line as follows:
1 1 2 1 3 1 4 2 1 1 1 4 4 5 1 3 3 4 5 1 5 3 4 4 3 5 5 1 3 4 2 1 1 1
Next separate them into row and column fractions again and find the new letter coordinates.
Our new encrypted cypher message is:
AFLRAD UCO VXTP VOFA
To decrypt just reverse this process.
*Note: Some encryptors break the original plaintext down into more manageable sections, such as groups of 4 or 5, and put the rows together in these sections. This also makes the cypher more secure.
The Binary code is a code that the computers recognize using only 1's and 0's. In the following example:
01010100 01101000 01101001 01110011 00100000 01100011 01111001 01110000 01101000 01100101 01110010 00100000 01101001 01110011 00100000 01100101 01100001 01110011 01111001 00100000 01100010 01110101 01110100 00100000 01110110 01100101 01110010 01111001 00100000 01110100 01101001 01101101 01100101 00100000 01100011 01101111 01101110 01110011 01110101 01101101 01101001 01101110 01100111 00100000 01110100 01101111 00100000 01100101 01101110 01100011 01110010 01111001 01110000 01110100 00100000 01100001 01101110 01100100 00100000 01100100 01100101 01100011 01101111 01100100 01100101
We simply use the tables below to decode and get the sentence:
"This cypher is easy but very time consuming to encrypt and decode"
You will notice that the first letter is a capital and uses the capital letter table and the rest uses the lower case table.
A=01000001 B=01000010 C=01000011 D=01000100 E=01000101 F=01000110
G=01000111 H=01001000 I=01001001 J=01001010 K=01001011 L=01001100
M=01001101 N=01001110 O=01001111 P=01010000 Q=01010001 R=01010010 S=01010011
T=01010100 U=01010101 V=01010110 W=01010111 X=01011000 Y=01011001 Z=01011010
a=01100001 b=01100010 c=01100011 d=01100100 e=01100101 f=01100110 g=01100111
h=01101000 I=01101001 j=01101010 k=01101011 l=01101100 m=01101101 n=01101110
o=01101111 p=01110000 q=01110001 r=01110010 s=01110011 t=01110100 u=01110101
v=01110110 w=01110111 x=01111000 y=01111001 z=01111010
Space=00100000 . (period)=00101110 , (Comma)=00100111 : (Colon)=00111010
; (Semi-Colon)=00111011 ? (Question)=00111111 ! (Exclamation)=00100001 -= 00101101
' (Apostrophe)=00101100 " (Quotation)=00100010 ( (Open Parenthesis)=00101000
) (Closed Parenthesis)=00101001 =(Equal Sign)=00111101 @=01000000 %=00100101
1=00110001 2=00110010 3=00110011 4=00110100 5=00110101 6=00110110
7=00110111 8=00111000 9=00111001 0=00110000
1=00000001 2=00000010 3=00000011 4=00000100 5=00000101 6=00000110
7=00000111 8=00001000 9=00001001 0=00000000
A book cipher is a cypher in which the key is some aspect of a book or other piece of text (newspaper, magazine, encyclopedia, etc); books being common and widely available in modern times, users of book ciphers take the position that the details of the key are sufficiently well hidden from attackers in practice. It is typically essential that both correspondents not only have the same book, but the same edition.
Traditionally book ciphers work by replacing words in the plaintext of a message with the location of words from the book being used. There are two basic and most widely used methods for a book cypher. The first lists the page number in the book followed by the word on the page. So a cypher of 4/244 would be the fourth page of the book and the 244th word on the page. The second most widely used method is to list the page number followed by the number of the sentence on the page followed by the word number in that sentence. So a cypher of 17/12/3 would be page 17, sentence 12 and the 3rd word in the 12th sentence. Another method for a one page document is the line/word format. So a code of 3/7 would be the third line and the 7th word in the 3rd line of that document. Some times book cyphers can be a little tricky because some coders use the titles of chapters as a word count or sentence count. (Note: if you are dealing with a one page document, the x/x/xx format could be paragraph/line/word instead of page/line/word).
Braille encryption uses a specific alphabet for visually impaired, composed of dots. Each letter corresponds to a combination of 6 points (embossed or not).
There are 2 major types of alphabets, the International alphabet and the French alphabet (which has specificities, for accented characters or numbers). See above chart.
The Caesar Cipher is a code Julius Caesar invented when he mailed letters. He invented it so if his messenger was robbed of that letter the robber wouldn't be able to read it. It is probably one of the most simple codes ever. It is 3 letters back so A would be X. The ROT Cipher is almost the same as the Caesar Cipher. The only difference is that Julius Caesar used a shift of -3 always instead of any other number and therefore it is called a Caesar Cipher.
A=X B=Y C=Z D=A E=B F=C G=D H=E I=F J=G K=H L=I M=J N=K
O=L P=M Q=N R=O S=P T=Q U=R V=S W=T X=U Y=V Z=W
Caesar Box Cypher
Using a Caesar Box cypher can be tricky but once you figure it out it is quite simple. Below is an example of an encrypted text:
The first thing you must do in a transposition cypher is count how many total letters there are in your encrypted code. In this example there are 35 encrypted letters. You divide this number by a number that will put them into equal boxes. 35/5=7. So we will set up a grid of 7 boxes wide and 5 boxes long down a page. We then start with the first letter in our encrypted code and write the letters in the top left box going across to the top right box in order. Once you have written the first 7 letters in the first 7 boxes across you come back to row two and write then next 7 letters across from left to right and so on. Once you have all the letters written in the boxes you will then be ready to read the code. To read the code you now read the columns down starting with the first column going down from the top and then wrapping around to the second column at the top down and so on. If your code has considerably fewer letters you may not need as many rows or columns to decode. If there are any un-needed "x's" at the end then disregard.
There are many types of transposition cyphers. Columnar, Rail Fence, Route Cypher, Double Transposition, Scytale etc.
The following is an example of a Columnar Cypher. The columnar transposition cypher is a fairly simple and easy to use cypher once you understand it. You must have a keyword sent to you along with a message to solve it.
In this example our keyword will be "German". And our encrypted sentence will be
The first thing you will do is write the keyword "German" in alphabetical order across the top of the page "AEGMNR" and then under that you will write the encrypted message in rows below the alphabetical "AEGMNR" as follows:
Once you have done this you will then rearrange the rows into alphabetical order for the word "German" also rearranging all accompanying rows with it as follows:
Then read the message starting with the top row from left to right. Continuing on to the second row from left to right and so on.
Our message will say:
"Defend the east wall of the castle"
When encrypting a message and you have extra spaces at the end of your sentence, you simply put x's in those spaces to account for that space. These will be disregarded by the decoder when decrypting as in the example above.
A Combination Cipher is a cipher using 2 or more codes. For example, if you wanted to make the best code ever, you could do Abtash, Caesar Cipher, Vigernere Cipher, and then A1Z26.
Francis Bacon Cypher
There are two ways to use the Francis Bacon cypher. The first is to simply use an AB method throughout the letter as follows:
First you have to separate all the AB letters into groups of five throughout the entire letter and then solve for each group of five like the following:
BAABA AABBB ABAAA BAAAB ABAAA BAAAB AAAAA ABBAA AABAA BABAB AAAAA ABABB ABBBA ABABA AABAA ABBAB AABAB BAABA AABBB ABAAA BAAAB BAABA BABBA ABBBA AABAA ABBAB AABAB AAABA BABBA ABBBA AABBB AABAA BAAAA BAABA AABBB AAAAA BAABA ABAAA BAAAB BAAAA AABAA AAAAA ABABA ABABA BABBA ABBBB BAABB ABAAA BAABA AABAA BAAAB ABAAA ABABB ABBBA ABABA AABAA ABBAB ABBAA AAABA AABAA BABBA ABBAB BAABB AABBA AABAA BAABA BAABA AABBB AABAA AABBB AAAAA ABBAA AABBA ABBAB AABAB BABAA ABBAB BAAAA ABAAB ABAAA ABBAA AABBA BAABA AABBB AABAA AAABA ABBAB AAABB AABAA AAAAA ABABA ABABA ABAAA BAABA BAABA AAAAA ABAAB AABAA BAAAB ABAAA BAAAB ABBBA AAAAA BAABA ABAAA AABAA ABBAA AAABA AABAA AAAAA ABBAA AAABB AAAAA ABABA ABAAA BAABA BAABA ABABA AABAA AABBB AAAAA BAAAA AAABB BABAA ABBAB BAAAA ABAAB
Using the following tables to decode for either a 24 letter or a 26 letter cypher:
Using a 26 letter system:
A=AAAAA B=AAAAB C=AAABA D=AAABB E=AABAA F=AABAB G=AABBA H=AABBB I=ABAAA J=ABAAB K=ABABA L=ABABB M=ABBAA N=ABBAB O=ABBBA P=ABBBB Q=BAAAA R=BAAAB S=BAABA T=BAABB U=BABAA V=BABAB W=BABBA X=BABBB Y=BBAAA Z=BBAAB
Using a 24 letter system:
A=AAAAA B=AAAAB C=AAABA D=AAABB E=AABAA F=AABAB G=AABBA H=AABBB I/J=ABAAA K=ABAAB L=ABABA M=ABABB N=ABBAA O=ABBAB P=ABBBA Q=ABBBB R=BAAAA S=BAAAB T=BAABA U/V=BAABB W=BABAA X=BABAB Y=BABBA Z=BABBB
Once we group them into five and use the table above we decode for:
"This is an example of this type of cypher that is really quite simple once you get the hang of working the code all it takes is patience and a little hard work"
The other way to use a Francis Bacon system is to hide a message inside a message. Both are relatively easy to detect and easy to solve. The second way uses different typeface in the sentence to hide the message, such as bold and regular type or italics. But this is easily seen by a reader. Typing a message as follows (I am italicizing the bold letters in this example to make them more visible but normally they would just be bold):
ITS A BEAUTIFUL DAY IN THE NEIGHBORHOOD
Breaking this sentence apart into groups of five, like the Francis Bacon cypher calls for:
ITSAB EAUTI FULDA YINTH ENEIG HBORH
All plain face text, non bold letters stand for "A's" and all bold face text stand for "B's" in this instance. The first set of five letters has a bold "I" and then regular type "TSAB" so we would look on our 26 letter chart and find the code for BAAAA. Which is "R". The next set is a regular face type of "EA" and then bold face type of "UTI" so we look on our chart for AABBB, which is "H". The next set is a regular type of "F" then bold type pf "UL" then regular type of "D" then bold of "A". We look on our chart for ABBAB and find "O". The next set is regular "YIN" and bold "TH". We look for AAABB and find "D". Next is regular type of "EN", bold "E", regular type of "IG". We look for AABAA and find "E". Next is bold "H" then regular type of "BOR" then bold "H". We have BAAAB and find "S".
Putting this word together and we spell "Rhodes".
In the history of cryptography, a grille cipher was a technique for encrypting a plaintext by writing it onto a sheet of paper through a pierced sheet (of paper or cardboard or similar). You then filled in the letter around these words with a document that makes sense when an outsider reads it and they can only find the cypher if they lay the grill over the top to find the coded words. Sir Francis Walsingham was notoriously famous for using this type of cypher to encode his correspondence during the Elizabethan times.
The keyboard code is just the order of letters on a keyboard. To decode it you just shift left, right , up or down. For the following example:
Just shift them all to the left and we get:
If there isn't a letter to the left or right you go the opposite direction. Same thing with up or down.
Mexican Army Cypher
The wheel of the Mexican army is in fact made up of 5 rotating concentric disks (also called wheels, or stages), whose position can be adjusted. Generally the outer wheel is fixed (the letters wheel) with the A at the top, so there are only 4 disks that are swiveling and adjustable.
The 4 disks are made of numbers from 00 to 99 as follows:
01, 02, 03, ..., 24, 25, 26
27, 28, 29, ..., 50, 51, 52
53, 54, 55, ..., 76, 77, 78
79, 80, 81, ..., 98, 99, 00, -, -, -, -
The fourth disk is composed of the numbers from 79 to 99, followed by 00 (for 100) and 4 empty slots (which may be called 101, 102, 103 and 104).
The position of the disks is the encryption key. The key (the position of the disks on each stage) is defined according to two methods:
- by a set of 4 numbers, those situated under the A, here 01, 27, 53, 79
- by a set of 4 letters, those above (on the outer disk) of the numbers 01, 27, 53 and 79 (which are the smallest numbers of each disk), here A, A, A, A
To encrypt a message with the Mexican Army Wheel at each letter of the plain message, the transmitter marks it on the outer dial and associates a two-digit (random) code among the 4 located just below the letter on each of the disks.
Example: Given a dial positioned at stage 1 on 01, at stage 2 on 27, at stage 3 on 53 and at stage 4 on 79 (which is the default position, therefore associated with the 4 letters AAAA).
To encrypt the message word "Cypher" the encryptor locates the "C" on the wheel which and chooses one of the four corresponding numbers in that line. So for "C" we can choose from 03, 29, 55, and 81.
For the next letter of "Y" we can choose from one of the following numbers in the "Y" line of 25, 52, 77, and one of the blank numbers that we can insert following in order which would be 103.
For the next letter of "P" we can choose from one of the following numbers in the "P" line of 16, 42, 68, or 94.
For the next letter of "H" we can choose from one of the following numbers in the "H" line of 08, 34, 60, and 86.
For the next letter of "E" we can choose from one of the following numbers in the "E" line of 05, 31, 57, and 83.
For the last letter of "R" we can choose from one of the following numbers in the "R" line of 18, 44, 70, and 96.
Our final encrypted cypher can read as:
032516080518 or 295242344144 or any combination of the numbers as long as you choose one number from each letter sequence.
To decode you simple set up your wheel with the "A" block and all the smallest numbers on each wheel under "A" and then decode for each set of numbers. It is noted that you do not have to set the wheel up the same way every time. You may vary how the wheel is set up and send a key with your encrypted text to let the person receiving the encrypted text know how to set up their wheel in order to decode.
Morse Code Cypher
Morse Code was created by Samuel Morse and designed to transmit letters across telegrams. He wanted frequently used letters to have short codes and less frequently used letters to have longer codes. When encrypting only letters and numbers will be encoded and the rest will be treated like spaces. When decrypting only the periods and hyphens will be decoded and the rest will be treated like spaces. When a letter is finished, the encoder ends with an empty sound or empty visual. When decoding a slash / or any separating character can be added for a space. A period . is used as a stop.
Pig Pen Cypher
The Pigpen Cipher was created by the Freemasons so they could keep documents safe. It was also used by the confederate soldiers during the Civil War. It is called The Pigpen Cipher because the boxes look like pigpens and the dots look like pigs. It seems complicated but it isn't really. The lines surrounding the letter and the dots within those lines are the symbols. Due to its simplicity it is often used in children's books on cyphers and secret writings.
Like the following example:
The phone code is really cool because not a lot of people know it. It is just the number the letter is on and then what number it is on that number. For example, A is on the 1st number on 2, so it would be 2 1.
A=21 B=22 C=23 D=31 E=32 F=33 G=41 H=42 I=43 J=51 K=52 L=53 M=61 N=62 O=63 P=71 Q=72 R=73 S=74 T=81 U=82 V=83 W=91 X=92 Y=93 Z=94
Polybius Square Cypher
Polybius square uses a 5x5 grid filled with letters for encryption.
As the Latin alphabet has 26 letters and the grid has 25 cells, a letter to remove is chosen, usually it's J, V, W or Z which are deleted. In this example we have combined I and J together.
The red numbers are labeling the lines of the Polybius Square and the green numbers are labeling the columns of the Polybius Square.
To decrypt the message 13 54 35 23 15 42 we simply find each letter in the coordinates.
For the first number of 13 we go to line (red numbers) 1 and then move over to column (green numbers) 3. These intersect at the letter "C".
For the number 54 we got to line 5 and then move over to column 4 and find the letter "Y".
We continue in this same method until we have solved and have the coded message as:
When using a keyword we enter the keyword skipping any repeating letters, then fill the remaining squares with the alphabet in order without repeating any of the letters in the keyword. In this example our keyword is "Secret". So we will use the letters "SECRT" and skip the second "E" because it is a repeating letter. We will enter these letters in the squares starting with the top left and going across. We then fill the remaining squares with the remaining alphabet in order minus the letters in our keyword of "SECRT". See example below. Because there are only 25 squares and 26 letters in the alphabet, generally the letter "J" is skipped or combined with the letter "I". We then follow the decoding directions above. Occasionally you will reverse this process and solve or encrypt using a column, line method instead of line, column method.
The QWERTY Cypher is a variation of the Keyboard Cypher but instead of shifting left, right, up, or down, the QWERTY cypher shifts using the set up of the keyboard. Using the top row of the keyboard, starting from the top left on the letter Q and moving right across the keyboard, it spells QWERTY and so on. So we will make the
Q=A, W=B, E=C, R=D, T=E, Y=F, U=G, I=H, O=I, P=J
Or in other words:
QWERTYUIOP = ABCDEFGHIJ
Then we move to the middle row on the keyboard and continue the alphabet.
A=K, S=L, D=M, F=N, G=O, H=P, J=Q, K=R, L=S
Or in other words:
ASDFGHJKL = KLMNOPQRS
Finally we move to the bottom row on the keyboard and finish up the alphabet.
Z=T, X=U, C=V, V=W, B=X, N=Y, M=Z
Or in other words:
ZXCVBNM = TUVWXYZ
ZIOL OL TQLN = THIS IS EASY
Rail Fence Cypher
The Rail Fence Cypher is a type of transposition cypher and is easy to apply. To decrypt a rail fence cypher we have to construct a diagonal grid. Start by making a grid with the same amount of rows as there are letters in the cypher text. You must also have a key to decrypt this cypher, in this case it is a number, for how many rows you will need. In the following example our key will be 4. Our cypher text that we receive in this example is as follows:
You will place your first letter of T in the top left box and then place the dashes (which will eventually be replaced with the remaining cypher text) in a diagonal going down and back up to the top line again, placing the next letter in the cypher text on the next top row box as follows:
Continuing row by row this will be the second stage:
We can now read the plaintext by following the diagonals in a W shape to get:
"they are attacking from the north"
Another type of Rail Fence cypher uses cycles. This type of cypher goes horizontally instead of vertically to solve. For this example of cypher text we will have four units. For the cyphers text of "HANRAGRUDENOH" with a height of 3 means the height of your grid will be three high. You will then count the total amount of letters in your cypher text. This cypher text has 13 letters, or units, so we will divide that number by 4. 13÷4=3.25 which is 3 full cycles. We round down to 3 cycles. Since we had to round down we include this extra cycle in the top row making the top row have 4 units. This will be the first 4 letters of the cypher "HANR".
. . . . . . . . . . .
. . . . . . . . . . .
The middle row is then calculated by the number of full cycles by 2. So 3×2=6. This becomes the number of units, letters, in the middle row, "AGRUDE".
. . . . . . . . . . .
The last row is is the number of full cycles multiplied by 1. So 3×1=3. This becomes the number of units, letter, in the bottom row, "NOH".
The final cypher reads:
Hang around her
The Rosicrucian Cipher is almost exactly like the Pigpen Cipher. The symbol that the letter is inside is the symbol that you put for that letter. Due to its simplicity it is often used in children's books on cyphers and secret writings.
Note: When using this printable wheel pay no attention to the numbers on the wheel. Use the letters on it only. I prefer this wheel because the letters line up well and make decrypting less confusing. Thank you.
The ROT-N Cipher is when you take a letter and put it back or forth to equal a different letter. An example of this would be -1 equals A = Z. +1 equals A + B. It is a relative to the Caesar Cipher. When working a ROT-N cypher, the N equals any shift number possible positive or negative. A positive shift would be turning your inner dial on your wheel (see link above) forward and a negative shift would be turning your inner dial backwards. So for a ROT-13 shift that is a negative, which is the most common, you would start with both dials on A=A. Then turn your inner dial backward 13 spaces until A=N. The inner wheel is for the coded letters that you are reading that don't make sense. And the outer wheel is the letters you are solving for.
GUVF VF RNFL
Those letters will now be the inner dial letters. You will be solving by taking the letters from the outer wheel that correspond. So that makes the G (from inner wheel) equal T (from outer wheel). The U (from inner wheel) equals H (from outer wheel) and so on. Until we solve for:
THIS IS EASY!
The most common shift is -13 but any other number can be used. If the shift was a +3 then the inner wheel A would then equal the outer wheel D. Doing a -3 shift A would equal X because we turned the inner wheel backwards instead of forward.
The above format is the most basic encryption technique but there are lots of ways to spice this cypher up. One such way is to use a progressive shift. You have a type of key with some type of numbers, possibly a date or time, and use those numbers repeatedly as your shift.
In the following example we will be using the time of 2:43am. Our cypher sentence will rotate every third letter a negative 2, every third letter a negative 4 and every third letter a negative 3 in order.
Our cypher sentence is:
VLLU MV C VRVEWKRJ ULLHX IQV WJMV ECSJIU
We start by shifting the alphabet on our wheel a negative 2 spaces because the first number in our key time of 2:43 is a 2. So A=Y. We now decode for V, making V=T.
Next we will shift our decoder wheel a negative 4 spaces because the next number in our time of 2:43 is 4 making A=W. Now we solve for L which is L=H.
Next we shift the alphabet on our decoder wheel a negative 3 spaces because the next number in our time of 2:43 is 3 making A=X. Now we solve for L which is L=I.
We continue this same pattern starting all over again until the entire cypher is decoded. We will have a decoded sentence of:
THIS IS A ROTATING SHIFT FOR THIS CYPHER
Semaphore Flag Signalling System
Semaphore Flag System is the telegraphy system conveying information at a distance by means of visual signals with hand-held flags, rods, disks, paddles, or occasionally bare or gloved hands. Information is encoded by the position of the flags; it is read when the flag is in a fixed position. Semaphores were adopted and widely used (with hand-held flags replacing the mechanical arms of shutter semaphores) in the maritime world in the 19th century. It is still used during underway replenishment at sea and is acceptable for emergency communication in daylight or using lighted wands instead of flags, at night. For information on the different flag positions for Semaphore please visit the link below.
A shift cypher is a type of cypher where the letter in the plaintext is replaced by a letter in some fixed number of positions down the alphabet. Some examples of shift cyphers are the Caesar, Abtash, and the ROT-N cypher.
A substitution cypher is probably one of the most common cyphers used. They work by replacing the letters of the alphabet by other letters, numbers, or even random symbols. The most commonly used is a mono alphabetic substitution cypher. Meaning that the shift does not change throughout the cypher. A mono alphabetic that is encrypted to C means that every time you see the letter C in the cypher text we replace it with the letter A in the plaintext. This can also be a fixed mono alphabetic cypher with symbols or numbers. Some examples of substitution cyphers are the Caesar, Abtash, and ROT-N cyphers. An example of a substitution cypher like the one below:
This decodes to "Hello how are you" in Greek language symbols.
Another type could be using times. If we start our time in a day normally at 12:00 then 12:00=A and this cypher will have 15 minutes increments. For the cypher sentence of
4:45, 1:45, 2:00, 4:30 2:00, 4:30 1:00, 12:00, 4:30, 6:00
Using the below decoded time grid:
Our plaintext sentence would read:
This is easy
We have simply substituted the alphabet for times.
Tap Code Cypher
The Tap Code Cypher which uses the Polybius square, has been used by prisoners, especially in Vietnam, to communicate by tapping on pipes or walls. To encode a letter, a prisoner would tap a number of times equal to the letter row, pausing, then a number of times equal to the letter column, then pausing again. The word "THE" would be "tap tap tap tap (pause) tap tap tap tap (pause) tap tap (pause) tap tap tap (pause) tap (pause) tap tap tap tap tap".
The Vigenere Cipher is a 26x26 grid with letters A-Z as the row and column heading. This table is usually referred to as the Vigenere Tableau, Vigenere Table, or Vigenere Square. The first row of the table has the 26 letters of the alphabet. The next row starts with the second letter and the letter A is at the end. The remaining rows follow in this suit as follows:
In addition to text the Vigenere also uses a keyword. In this example we will use the text of MICHIGAN TECHNOLOGICAL UNIVERSITY and a keyword of HOUGHTON.
The first thing we do is repeat the keyword under the original sentence repeatedly until all letters have the keyword under it, even if the keyword is interrupted as follows:
Separate the sentence and the keyword into sections of five letters as follows:
To encrypt pick a letter in the plaintext sentence and its corresponding letter in the keyword, use the keyword letter and plaintext letter as the row index and column index, and the entry at the row-column intersection is the letter in the cypher text. For example, the first letter in the plaintext is M and the corresponding keyword letter is H. This means that the row of H and the column of M are used, and the entry of T at the intersection is the encrypted cypher as below:
Since the letter N in MICHIGAN corresponds to the letter N in the keyword, the entry at the intersection of row N and column N is A which is the encrypted letter in the cypher text as follows:
Repeat this process until all plaintext letters are encrypted, and the cypher text will read:
TWWNPZOA ASWNUHZBNWWGS NBVCSLYPMM
To decrypt, pick a letter in the cypher text and its corresponding letter in the keyword, use the keyword letter to find the corresponding row, and the letter heading of the column that contains the cypher letter is the needed plaintext letter. For example, to decrypt the first letter T in the cypher text, find the corresponding letter H in the keyword. Then the row H is used to find the corresponding letter T and the column that contains T gives us the plaintext letter M (see images above).
Wig Wag Cypher
Wig Wag was used in the civil war to communicate during battles. It is pretty easy to do, you just have to remember that you don't have to write out all of some words.
During battle there were three positions that a flag, torch, or disk would use held by a signalman. All begin with the signalman holding the flag, torch, or disk motionless and vertical above his head.
Motion 1 was initiated by bringing the device downward to the right side and then back up to the start position of straight above their head.
Motion 2 was initiated by bringing the device downward and to the left side and then back to the start position.
Motion 3 was lowering the device down in front of the signalman and then restoring to original start position.
The wheel below shows the numbers used for each letter.
"A" would be 1..1..2 so down to the right and back to start position. Down to the right and back to the start position. Down to the left and back to start position.
There are other variations of the alphabet other than this wheel.