Sams Teach Yourself Java 2 in 21 Days, Second Edition

Objects and Classes

Object-oriented programming is modeled on the observation that in the physical world, objects are made up of many kinds of smaller objects.

However, the capability to combine objects is only one aspect of object-oriented programming. Another important feature is the use of classes.

A class is a template used to create an object. Every object created from the same class will have similar, if not identical, features.

Classes embody all features of a particular set of objects. When you write a program in an object-oriented language, you don't define individual objects. Instead, you define classes used to create those objects.

For example, you could create a Modem class that describes the features of all computer telephone modems. ...