The real world is a messy place, and software reflects this to some extent. This messiness, however, doesn't mesh well with the general tendencies of software developers, who like to try to simplify the world with assumptions. When those assumptions later turn out to be wrong, bad things happen.
In this talk, we'll discuss three perennial sources of bad developer assumptions: floating point numbers, dates and times and the names of people, places, and things.
We'll illustrate why each of several commonly-made assumptions is incorrect, show how to use Ruby to arrive at the correct answer, and empower you to make better decisions about your code in the process.