By declaring the method "main" as a static method, it does not act upon an instance of the class. In other words, you don't have to have an object created to use the main method. Obviously, it would be hard to create an object (an instance of the class) before the program starts. That's how I rationalize in my mind the reason for declaring the main method as static.
Also, Sun has declared that main() should have this signature: public static void main( String args ). If you use the wrong signature, there is a high probability that your program will not run because the JVM will not be able to find the main() method, and therefore will not be able to start the application.
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