A boolean function is like a math equation. It is a type of math problem with only two possible answers: yes or no, true or false. An example of a boolean function is x + 2 = 4. In this equation, x can equal 2, which would make it true, or it could equal 5, which would make it false. Boolean functions are used in computer programming to help the computer decide what to do when it encounters different kinds of data. For example, if the computer needs to know whether a number is greater than 5, it can use a boolean function to determine if this is true or false.