Part I: Code and Cryptogram Strategies
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✓ If you have a vowel, the consonant that most often fol-
lows it is N: AN, EN, IN, ON, UN — they’re all popular!
✓ The most common three-letter words in English are AND
and THE (see, each appears twice in this sentence!).
✓ The most common four-letter word in English is THAT.
✓ The most frequently seen double letters in English are
LL, followed by EE, SS, OO, TT, FF, RR, NN, PP, and CC.
✓ Two-letter words always have at least one vowel, and are
almost always one consonant and one vowel.
✓ Letters that appear fairly evenly throughout a ciphertext
are more likely to be vowels.
✓ Forty percent of any English message is vowels, give or
take just 1 percent either way.
✓ Letters that appear less often and are linked with a few
repeating characters are more likely to be consonants.
For example, K appears after C, L, N, R, and S, and the
vowels, but rarely with other letters.
If you’re interested in discovering a bigger list of letter fre-
quencies, common letter patterns, and further discussion on
this fascinating topic, check out Word Searches For Dummies
by Denise Sutherland (Wiley).
Pattern words
Pattern words are a crucial part of cracking any cipher.
They’re simply any word that has repeated letters in it (not
just double letters, although those are good, too). The pattern
these repeated letters create makes it possible to hunt for the
words in an encrypted text.
THAT is the most common pattern word. Any cipher word
that’s in the pattern 1 - - 1 is almost definitely THAT (see, the
T appears twice).
Check out dictionaries of pattern words (The Cryptogram
Dictionary by Lloyd MacCallum is one you may like). These
useful books can tell you all the words that fit the 1 2 2 1 -
pattern, for example (ASSAY, DEEDS, KOOKY, TEETH, and
TOOTH, just in case you were wondering). The numbers rep-
resent the repeating letters.