The entry point of every Java program is:
public static void main(String[] args)
Each word has a specific purpose:
public means the method is accessible from outside the class. The JVM needs this access to call it.
static means the method belongs to the class itself, not to an instance. The JVM calls main before any objects exist.
void means the method returns nothing.
main is the exact name the JVM looks for. Spell it differently and nothing runs.
String[] args is an array of command-line arguments. If you run java MyApp hello world, then args[0] is "hello" and args[1] is "world".