Input is a 4x4 table with letters. One starts from any of the 16 elements and can move in one step to any of the 8 neighboring cells not visited before (up, down, left, right, up-left, etc, no hyperspace jumps between rows 1 & 4, columns 1 & 4). Every time step is made letter in that cell is added so a word is built as we walk. These generated words are looked up in external dictionary (function to look up in the dictionary is provided, I did not understand significance of this dictionary well) and the goal of the exercise is to output all words generated by all possible table walks and which are contained in the dictionary.