Pinprick Cipher

The Pinprick cipher is probably one of the easiest codes to crack, but only if you are looking for it. It is used in a normal letter, written on paper, or book and there is a pin prick under the letters that you want to write the message with. For example if you wanted to write "Meet me at midnight" you would find a book or letter with all of those letters in that order and then put a tiny hole with the pin underneath the letters.