An array is a group of variables (called elements or components) containing values that all have the same type. Recall that types are divided into two categories—primitive types and reference types. Arrays are objects, so they are considered reference types. As you will soon see, what we typically think of as an array is actually a reference to an array object in memory. The elements of an array can be either primitive types or reference types (including arrays, as we will see in Section 7.9). To refer to a particular element in an array, we specify the name of the reference to the array and the position number of the element in the array. The position number of the element is called the element’s index or subscript.