Marker Interfaces in Java

http://javarevisited.blogspot.com/2012/01/what-is-marker-interfaces-in-java-and.html

Looking carefully on marker interface in Java e.g. Serializable, Clonnable and Remote it looks they
are used to indicate something to compiler or JVM. So if JVM sees a Class is Serializable it done some
special operation on it, similar way if JVM sees one Class is implement Clonnable it performs some operation
to support cloning. Same is true for RMI and Remote interface. So in short Marker interface indicate, signal
or a command to Compiler or JVM.

In summary marker interface in Java is used to indicate something to compiler,
JVM or any other tool but Annotation is better way of doing same thing.