Ever wanted to send a message but not let anybody else know what you are saying

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Ever wanted to send a message but not let anybody
else know what you are saying? For thousands of
years people have been doing just that. They
do it using codes.
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The ancient Egyptians and Greeks used codes to
create secret messages. Mary Queen of Scots sent
letters in code. During World War II the Nazis
used the Enigma code machines to encipher their
messages. Allied mathematicians and
cryptographers worked on breaking the Nazi secret
codes. They were able to build replicas of the
German Enigma machine which they used to decipher
Nazi radio messages.
Enigma Machine
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One of the easiest codes you can use is the
alphabet up one code. This is when you want
the letter A but use the letter B instead. If you
want B, you would use C. For C - use D and so on
up until Z which moves up one to become A.
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Here is a grid to explain how the code
works A B C D E F G H I B C D E F G H I J
J K L M N O P Q R K L M N O P Q R S S T U V W X
Y Z T U V W X Y Z A If you break this code -
ZPV XJMM VOEFSTUBOE UIJT NFTTBHF
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You can use the alphabet up two code or the
alphabet back one code. You can use any code
you like as long as the person receiving the
message knows what code you are using. You
should make a grid for the alphabet up two or
the alphabet back one. When you have done
this, you should write a message for a friend.
See if they can understand what your coded
message says.
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Another famous code is the numbers for letters
code. In this code we use 1 instead of A, as A
is first in the alphabet. We use 2 instead of B,
as B is second in the alphabet.. and so on all
the way up to 26 instead of Z, as Z is the twenty
sixth number in the alphabet. 3 - 1 - 14
25 - 15 - 21 6 - 15 - 12 - 12 - 15 - 23
20 - 8 - 9 - 19
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If you make things really difficult for
codebreakers, you can combine the two codes and
do the alphabet up one numbers for letters
code. Instead of A we use B . but B is second
in the alphabet, so A becomes 2. B moves up one
to C but C is third in the alphabet and so on.
This is not easy, so the best thing to do is
write out a grid. A B C D E F G H I
2 3 4 5 6 7 8 9 10 J K L M N O P Q R 11 12 13 1
4 15 16 17 18 19 S T U V W X Y Z 20 21 22 23 24 2
5 26 1 Notice that Z moves up in the alphabet to
A, so becomes the number 1
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Playing with codes is great fun. Be careful that
you dont make up a code that is so difficult to
break that nobody can work out what you are
saying. REHTONA SUOMAF EDOC is the back
to front code. This is where the words are all
spelled back to front. If I want to use the word
SPY, I reverse the letters and get YPS.
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If you are really good with codes, you can do
complicated things like replace the letters of
the alphabet with numbers but do it in reverse
order.
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A is the first letter of the alphabet but we will
use the number 26 B is the second letter of the
alphabet but we will use the number 25 We
continue this pattern all the way up to the
letter Z Z is the twenty sixth letter of the
alphabet but we will use 1 A B C D E F G H I 26 2
5 24 23 22 21 20 19 18 J K L M N O P Q R 17 16 15
14 13 12 11 10 9 S T U V W X Y Z 8 7 6 5 4 3 2
1 12 13 15 2 22 3 11
22 9 7 8 24 26 13 24 9 26
24 16 7 19 18 8 24 12
23 - 22
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Squared number codes Do you know your squared
numbers? If you square the first ten numbers,
you get 1 4 9 16 25 36 49 64 81 100 Can you
tie squared numbers to the letters of the
alphabet to create the squared number code? A
1 B 4 C 9
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A B C D E F G H I 1 4 9 16 25 36 49 64 81
J K L M N O P Q R 100 121 144 169 196 225 256 28
9 324 S T U V W X Y Z 361 400 441 484 529 576 6
25 676 400 64 25 16 81 196
196 25 324 144 1 16 625 81 361
1 361 256 625
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Although this looks quite difficult, the first
thing a good code breaker would notice is that
all the numbers are squared numbers. When you
spot this, breaking the code becomes much
easier. The first thing a good code breaker
looks at is the set of numbers and if they can
spot that all the numbers are even, odd, squared,
prime or members of any other set of numbers,
they know where to start when breaking the
code. 28 30 46 26 2 22 10
50 30 42 36 30 46 28
6 30 8 10 38