We've seen how to combine two sets with the union operation, and find their common elements with the intersection operation. The logical next step is to see how the sets differ. Next, we'll take a look at how to find out what elements one set has that another doesn't. This operation is called a difference of two sets. An element is in the difference of two sets, if it is in the first set, but not the second.
In this recipe, we'll take a look at how to find the difference between two Set instances.
