☕ What is Java?

Java is a high-level, object-oriented, platform-independent programming language developed by Sun Microsystems in 1995 (now owned by Oracle). It follows the WORA principle — “Write Once, Run Anywhere”.

📝 Code Explanation (Line by Line)

Line	Explanation
`public class HelloJava`	Declares a class named HelloJava. In Java, all code must be inside a class.
`{`	Opening brace marks the beginning of the class body.
`public static void main(String[] args)`	The main method – it's the entry point of every Java program.
`public`	Makes the method accessible from anywhere.
`static`	Means the method can run without creating an object of the class.
`void`	Indicates the method doesn't return any value.
`String[] args`	Used to accept command-line arguments.
`System.out.println("Hello, Java!");`	Prints the text on the screen. System.out is the standard output stream.
`}`	Closing braces end the main method and class body.

🔑 Java Terminologies

JDK (Java Development Kit) → Tools for developing Java applications (includes JRE + compiler)
JRE (Java Runtime Environment) → Required to run Java applications (includes JVM + libraries)
JVM (Java Virtual Machine) → Runs the Java bytecode, making Java platform-independent
Bytecode → Intermediate code generated after compilation (understood by JVM)

🖨️ Printing in Java

You can print in Java using the following methods:

System.out.print("Text you want to print");
System.out.println("Prints new line after text");
System.out.print(456);
System.out.println(7+21);

Comments

Single-line Comments:

Single-line comments start with two forward slashes (//). Any text between // and the end of the line is ignored by Java (will not be executed).

// This is a comment
System.out.println("Learn Java");

Multi-line Comments:

Multi-line comments start with /* and ends with */. Any text between /* and */ will be ignored by Java.

/* The code below will print the words Hello World
to the screen, and it is amazing */
System.out.println("Comments make code more readable");