Many people play lotteries of various kinds. Lotteries are big business. People use lots of different strategies for choosing number combinations to play in these lotteries, but if any of those strategies really worked, the lottery business would shut down. However, although there are no really good strategies for winning lotteries, there are lots of really bad strategies, strategies that give the player an even worse chance of winning than if they were to simply choose random entries with no strategy at all. The basic rule is to avoid entering duplicates of possible winning combinations. This book provides computer programs that identify collections of possible lottery entries with minimal duplication of combinations.