Jotto

Jotto (or Giotto) is a word game. Each player picks a secret word of five letters, and they take turns guessing the other's word. When you guess a word, you find out the number of correct letters, but not their positions. So if you guess PEACH and the secret word was OTHER, you get a reply of 2 (for the E and the H, even though they're in the wrong positions). The name of the same computer game is Josho.

Variations

• The most popular variation uses words of four letters instead of five.

• Six-Letter (sometimes called 'Word Mastermind', though its logical content places it well beyond Mastermind and Jotto). Known to have been played with pencil and paper in UK computer departments at least as far back as 1970. Each player picks a secret word of 6 letters, and they take turns guessing the other's word. Secret words (sometimes called 'targets') and guesses, must all be real words verifiable in a nominated dictionary. When you guess a word, you find out the # of letters which are perfect matches only. So if you guess PEACHY and the secret word was OTHERS, you get a reply of 0 (because the E and H are in the wrong positions). Unlike Jotto et al, this game stretches one's skills in combinatorial logic as well as one's command of the dictionary. The name of the same computer game is Sixicon by Island Software, 1979.