With over 300 puzzles with a great variety of themes (20 letters by 20 letters, with never fewer than 25 terms), The Complete Idiot's Guide® to Word Search Puzzles provides hours of fun. In addition, many people believe that working word puzzles improves concentration, vocabulary, and problem-solving skills. Everyone knows the feeling of going blank on just the right word from time to time. It's this feeling that accounts for much the popularity of word search puzzles. Teachers have been using them for years for this very reason.