Writing reliable code means understanding bounds. Only a finite amount of memory is available for computation, only a finite amount of time exists to do it, and every object we store and modify must be finite. Resources are similarly bounded. Stacks are bounded, queues are bounded, file system capacity is bounded, and even numbers are bounded. This makes the world of computer science very different from the world of mathematics, but too few people take this into account when they write code. © 2015 IEEE.