Part I: Code and Cryptogram Strategies
32
These letters have long been used to create memorable
phone numbers. You know the sort of thing: “Call 1-800-MORE-
COFFEE now for more coffee!” This is a simple letter-to-number
encryption of the phone number 1-800-6673-263333.
In this book, however, we go in the opposite direction, from
number to letter.
You’re probably already all too familiar with using your cell-
phone keypad to type text messages. Most phones use predic-
tive text now, in which the phone’s software guesses at what
you mean when you input a certain number sequence. This
guess is based on common words used in English.
For example, to type HOME, you press 4663. However, this
combination of number keys also encodes the words GOOD,
GONE, HOOD, HOOF, and several less-common words.
The fiendish Text Message Ciphers in this book take advan-
tage of this ambiguity. They’re simply a collection of numbers,
made to type a secret message. Your job is to figure out what
the intended words are!
Look for common patterns, such as 843 (THE), 263 (AND), and
8438 (THAT) within these ciphers.
Because each number can represent three or four different
letters (unlike in a substitution cipher, where each symbol
represents a single letter), you have to try several letter
options for each word.
The context of the message helps you decipher these puzzles.
For example, with the message 7323 8447 2665, the first two
words are pretty easy to pin down: READ THIS. However,
2665 is more problematic; it can be COOL, COOK, or BOOK.
Obviously, the first two words indicate that the correct mes-
sage is READ THIS BOOK, because READ THIS COOL doesn’t
make sense. (Or does it? Maybe we can start a new fad here!)
Use your cellphone to help crack these codes. Start a new
text message (that you won’t send to anyone), and type in the
numbers to see which words are options.