ABSTRACT
In Chapter 4 you learned about Java's primitive data types and about the String class. The Java primitive data types serve to store a single alphanumeric or Boolean value. For example, you can use an int data type to store a whole number, or a float type to store a decimal number. But computer programs often need to store and manipulate data in groups of associated values. For example, a payroll program keeps track of the names, addresses, social security numbers, number of dependents, wages, and other items of information necessary for managing the company's employee database.
