public static void main is the standard entry point for a Java program. It tells the Java Virtual Machine where to start running the code.

What each part means

  • public: The method can be accessed from outside the class, so the JVM can call it.
  • static: The JVM can run it without creating an object first.
  • void: The method does not return a value.
  • main: This is the fixed method name the JVM looks for when starting a program.
  • String[] args: This lets the program receive command-line arguments.

Why it matters

Without this exact method signature, a standalone Java program usually will not start from the command line because the JVM looks for that specific entry point. In simple terms, it is the program’s starting door.

Example

java

public class Main {
    public static void main(String[] args) {
        System.out.println("Hello, world!");
    }
}

Important note

The order of public and static can vary, but void, main, and the parameter list must still be in the expected form for the JVM to recognize it as the startup method.