Up until this point, when we spoke of distributions, we were referring to frequency distributions. However, when we talk about distributions later in the book--or when other data analysts refer to them--we will be talking about probability distributions, which are much more general.

It's easy to turn a categorical, discrete, or discretized frequency distribution into a probability distribution. As an example, refer to the frequency distribution of carburetors in the first image in this chapter. Instead of asking *What number of cars have n number of carburetors?*, we can ask, *What is the probability that, if I choose a car at random, I will get a car with n carburetors?*

We will talk more about probability (and different ...