Gaps is one of my favorite solitaire card games. You're trying to arrange the cards in order from 2 - King by suit. The game starts by the cards being dealt into 4 rows, with the deuces moved to the far left side. The Aces are removed to create gaps that you can move other cards into. You can move a card into the gap if it is one less than the card to the right and of the same suit, or one more than the card to the left and of the same suit. As you get cards in order starting with the deuces on the left, they get highlighted. These cards won't be shuffled when you click the shuffle button. You almost always get stuck before you have arranged the cards in order, and you are allowed up to three shuffles per game. This picks up and shuffles all the unhighlighted cards so you can continue to move cards around with the hope of winning. You win the game if you can build up the rows from 2 - King by suit.