->public -> To call by JVM from anywhere. It is possible that
JDK can be installed on your system anywhere and java program
is saved on another drive. So to be called by JVM from anywhere
main() method must be public.
->static -> A static method can be called without existing object.
main() method in any way is not related to any object. If main()
method is not static, JVM will have to create an object of the
class and then JVM will be able to call main() method. It will
add an extra work to JVM.
->void -> main() method is called by JVM and main() method doesn't
return anything to JVM.
->main -> This is the name which is configured inside JVM.
->String[] args -> command line arguments.
