The public reserved word in Java is one of 4 visibility or accessibility modifiers. These modifiers restrict access to the members (variables or methods) to which they are applied. Classes or members declared public can be accessed by any other class. Classes or members declared private can only be accessed by the class itself. Classes or members declared protected can only be accessed by the class and any of its subclasses. By ommitting any visibility modifier, you declare the class or member to be of default visibility. This forth modifier allows access from any classes in the same package as the current class.