This is my third encoder. It works with each letter equalling another, or monoalphabetically. Click one of the white letters up the top, then click the tick to put the first letter in the alphabet in, and repeat until all letters are done. Alternatively, click one of the presets to the left of the first blue letter. Once one of these are done, then you can choose Encode Mode or Decode Mode and start to type. Left is backspace. Down the bottom will be two alphabets: Encode on the top and Decode on the bottom. (Please note that the Encode and Decode alphabets correspond to the real alphabet, eg: Q is the first letter of the Encode alphabet down the bottom, so that means it corresponds to the first letter of the real alphabet, or A.) Have fun coding! ~Abrulz