Space limits us, so that we try to accommodate by giving titles and tips. Enciphered tips are those that are optional for solving. They are enciphered so that those who want the greater challenge can ignore them. The Caesar shift is not normally more than five in either direction. Unless the tip is simply giving the period of the cipher, it is always found somewhere in the message.
Many ciphers use a keyword to develop their particular jumble of letters.
Recovery of the keyword offers an alternative or parallel path to solution alongside direct recovery of the plaintext. As the plaintext is revealed, so is the keyword, and guessing a letter in one will give a letter in the other that might aid solution. Keywords are dealt with in more detail in Chapter 7 . 2nd and final, also scattered throughout. 3rd from end.