Java is an object-oriented programming language centered around classes and objects, which serve as blueprints and instances of data types, respectively. Key concepts include encapsulation, inheritance, polymorphism, and abstraction, alongside access modifiers that control visibility. Understanding these foundational elements is essential for effective Java programming.

1. JAVA CLASSES AND
OBJECT

2. Introduction
 Java is an object-oriented
programming language.
 Classes and objects are
fundamental concepts in Java.

3. What is a Class?
 A class is a blueprint for creating
objects.
 It defines a datatype by bundling data
and methods that operate on the data
into a single unit.

4. What is an Object?
 An object is an instance of a
class.
 It has state (fields) and behavior
(methods).

5. Key Concepts
 Encapsulation: Bundling data and methods
within a class and restricting access using
access modifiers (private, public, etc.).
 Inheritance: Mechanism where one class can
inherit fields and methods from another class.
 Polymorphism: Ability to present the same
interface for different underlying forms (method
overloading and overriding).
 Abstraction: Hiding complex implementation
details and showing only the necessary features
of an object.

6. Access Modifiers
 public: Accessible from anywhere.
 private: Accessible only within the class.
 protected: Accessible within the same package
and subclasses.
 default (no modifier): Accessible within the
same package.

7. Conclusion
 Classes and objects are core components of
Java's object-oriented programming.
 Mastering these concepts is crucial for
effective Java programming.