Here are the key concepts of Object Oriented Programming: - Object: An object represents a real world entity with attributes and behaviors. Ex: Person, Bank Account etc. - Class: A class defines the common attributes and behaviors of objects. It acts as a blueprint to create objects. - Encapsulation: Wrapping up of data and methods into a single unit called class. It hides internal details and represents as a single unit. - Inheritance: Ability to create new classes from existing classes by extending their features. New classes inherit attributes and behaviors of parent classes. - Polymorphism: Ability of an object to take multiple forms. Same method can act differently depending on the object that inv