Sample content This team paper explains the following concepts with examples: 1. Class 2. Objects (instances) 3. Instance Variables (attributes or properties) 4. Interfaces 5. Encapsulation 6. Inheritance 7. Polymorphism. Class: A class indicates a category of items, as well as acts as a model for producing this kind of items. A class models an abstraction by defining the characteristics as well as behaviors for the items symbolizing the abstraction. The characteristics of an item of a class are also known as features, as well as are described by fields in Java. A field in a class definition is a variable that can store a value which represents a specific property. The behaviors of an item of a class are also called operations, as well as are described using methods in Java. Fields as well as methods in a class definition are jointly called members. For instance we are thinking about a class CharStack to show the different ideas of object-oriented programming. //