This chapter contains the kind of information I wished I'd have paid more attention to when I began to make my first few games because it would have saved me a lot of hard work. When people sit down and think about how to make a game, they often consider the kinds of graphics to use, the sorts of levels to be encountered, and the types of enemies players must face. It's easy to get lost in the excitement of creativity and forget that games need ways of storing and sorting data. For this reason, it's easy to underestimate the importance of the subjects considered in this chapter. Once you begin to program a game beyond the superficial levels, you will notice the common problem of data storage and organization rearing its ugly head. If you are well versed in lists, heaps, and sorting, however, you will be in a better position than most to handle these sorts of problems.