Explain the signature `public static void main(String[] args)` piece by piece.

It is the entry point the JVM calls to start your program. public means the JVM can call it from outside the class; static means it runs without first creating an object of the class; void means it returns nothing; main is the fixed name the JVM looks for; String[] args is the array of command-line arguments passed to the program. If this exact shape is missing, `java` fails with an error that it cannot find or launch main.