 <p>There are four kinds of Class relationships</p> <ol> <li>Association: <strong>uses a</strong><br> Ex:a Class Man uses a Class Pen</li> <li>Aggregation: <strong>has a</strong><br> Ex:a Class Man has a Class Car ( Car is still there when Man die )</li> <li>Composition: <strong>owns a</strong><br> Ex:a Class Man owns a Class Heart ( When Man die, Heart die )</li> <li>Inheritance: <strong>is a</strong><br> Ex:a Class Man is a Class Human ( Man is a Human )</li> </ol> <p>A relationship between classes of objects </p> <p><strong>Inheritance>Composition>Aggregation>Association</strong></p>