The goal of solving the puzzle is to write different words, letter-by-letter, in the white squares. Next to the grid is a list of clues. The answer to each clue is a word or sometimes a phrase. The place in the grid where the answer to each clue should go is shown by a number and the direction in which the answer appears, for example, "1 Across" or "15 Down". Many computer programs have been created to find the answers to these clues.