Recall from Section 3.2 that each object of a class maintains its own copy of every instance variable of the class. There are variables for which each object of a class does not need its own separate copy (as you’ll see momentarily). Such variables are declared
static and are also known as class variables. When objects of a class containing
static variables are created, all the objects of that class share one copy of those variables. Together a class’s
static variables and instance variables are known as its fields. You’ll learn more about
static fields in Section 8.11.