Java Hello World Program

Let's write, compile and run the simplest Java program, and understand every word in it.

Java

class Simple {
    public static void main(String[] args) {
        System.out.println("Hello World");
    }
}

Hello World

Understanding the Program

Keyword	Meaning
`class`	Declares a class. Every Java program has at least one.
`public`	Access modifier: visible to everyone, so the JVM can call `main`.
`static`	Lets `main` run without creating an object.
`void`	`main` returns nothing.
`main`	Entry point of the program.
`String[] args`	Command-line arguments.
`System.out.println()`	Prints text followed by a new line.

Common mistakeJava is case-sensitive. system.out.println or Main vs main will cause errors.

Which method is the entry point of a Java program?

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