Bookworm is a word-forming computer puzzle game by PopCap Games. From a grid of available letters, players connect letters to form words. As words are formed, they are removed from the grid and the remaining letters collapse to fill the available space. As in Scrabble, players earn more points by creating longer words or words which use less common letters and earn less for smaller words. In November 2006, PopCap Games released a sequel, Bookworm Adventures. Bookworm was released for the Nintendo DS digital distribution service DSiWare on November 30, 2009. It has also been released on the regular Nintendo DS cartridge.