Cryptogram Classics

• Special characters (accented letters, etc.) are changed to their A-Z version 

• Capitalization is preserved with the use of "big caps" and "small caps" instead of uppercase and lowercase (this means "AaBbCc" will look like "AABBCC")

• No letter can be encoded to itself (A can be B-Z but not A, and Z can be A-Y but not Z, etc.)

• Two letters cannot be encoded to the same letter (A can be C and B can be C but BOTH A and B cannot be C). Every letter A-Z is encoded as a different and unique letter A-Z.

• Each page is a new puzzle with a new key (if A = N on one page it is very unlikely for A = N on the next page, but it is possible). One page's key has no relationship to the key on any other page.

First, think about how the source language works. Here I will be talking about English in general but if the source text is British English then expect British spellings, etc. 

Language Rules: There are many rules over when words are used. For example "am" is always going to be after "I" in a sentence (and before "I" in a question). The word "hi" is more likely to be in dialog or quotes instead of normal story text. Capitalized words are proper nouns (the names of certain people, places, things, or ideas), the pronoun I, or the start of a sentence.

Second, start with words that are only one or two letters long and around numbers and apostrophes, and try to find "TH".

One-letter words: either "a" or "I".  You know "I" should always be capitalized, and it will appear in different ways than "a".

Two-letter words: while there are over 100, the vast majority of the time it will be one of these 19: am, an, as, at, by, do, go, hi, if, in, is, it, me, my, no, of, on, or, to. (You can see five use "I" and four use "a", so you can compare them to the one-letter words).

Numbers: other two-letter words appear with numbers: think of words after years AD/BC/BCE/CE, or words that appear after ordinal numbers st/nd/rd/th (like dates). 

Apostrophes ('): There are only so many words with them. If it's alone at the end of the word you can easily assume the the end of the word is  "in'" if the word isn't capitalized (if not then it's probably a name that end with "s" with a possessive apostrophe - like "The Adams' cat" ).

Let's look at the options with examples:

• 'X : "X" could be "S", "D", "T", or "M" (if it's "T" or "M" we also know the letter before is "N" or "I", respectively)

• 'DD : "D" is "L"

• 'QW :  "QW" is either "RE" or "VE" (either way "W" here is "E")

Think about what these conjunctions mean and the type of words that get an apostrophe:

• 's  = "is" / "has" / ownership = he (is / has), she has, names & nouns (cat's toy / Mike's cat/ Mr. Adams' cat)

• 'd = "had" / "would" =  I (had/would), he (had/would), she (had/would), we (had/would), they (had/would).

• n't = not = can (not), was (not), would (not), should (not), could (not), had (not), etc.

• 'm = am = I (am)

• 'll = will = I (will), he (will), she (will), they (will), we (will), names & nouns (the dog'll bark/ Mike'll call/ Mr. Adams'll come)

• 're = are = they (are),  we (are) 

• 've = have = I (have), they (have), we (have)

Why look for "TH": many common words include one or both together. The most common three-letter word is "the", and common four-letter words include: this, that, then, than, they, and them. Depending how you calculate it "T" could be considered the second most commonly used letter in English (by the same metric, "H" is 8th). Finding T and H will let you figure out many three, four, and bigger words.