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 1. Introduction to Java:

   - Java is a popular, object-oriented, high-level programming language developed by Sun Microsystems (now owned by Oracle) in the mid-1990s.

   - Known for its “write once, run anywhere” (WORA) philosophy, enabling platform independence through the use of the Java Virtual Machine (JVM).


1.1. Java Virtual Machine:

   - JVM is a crucial component of the Java platform that enables Java bytecode to be executed on various hardware and operating systems.

   - It acts as an interpreter between the platform-independent Java bytecode and the underlying system.

   - Example: When you run a Java program, the JVM translates the bytecode into machine code specific to your operating system and executes it.


1.2. Java Development Kit (JDK):

   - The JDK is a software development kit that includes all the tools required to develop, compile, and debug Java applications.

   - It contains the Java compiler (javac), JVM, standard libraries, and other development utilities.

   - Example: Developers use the JDK to write Java code and create executable Java applications.


1.3. Java Runtime Environment (JRE):

   - The JRE is a subset of the JDK and includes only the JVM and essential class libraries needed to run Java applications.

   - It is intended for end-users who only need to run Java applications, not develop them.

   - Example: When you install a Java application on your computer, you also need to have the JRE to execute the application.


1.4. Integrated Development Environment (IDE):

   - An IDE is a software application that provides comprehensive tools and features to facilitate the development of software.

   - IDEs enhance productivity by offering code editing, debugging, testing, and project management capabilities in one integrated environment.

   - Example: Eclipse, IntelliJ IDEA, and NetBeans are popular Java IDEs that provide code auto-completion, refactoring, and debugging features to help developers write Java code efficiently.


Example Java Code Snippet (Hello World):

```java

Public class HelloWorld {

    Public static void main(String[] args) {

        System.out.println(“Hello, World!”);

    }

}


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