Answer Posted / ajay tiwari

Marker interfaces are those interface which may contain any
method but they provide some special information to the JVM
about what type of class or object it can be.

EX. Cloneable is a marker interface with no method which
means but it provide information to the JVM that class's
object who implement it can be cloned.

Runnable is also a marker interface with a run() method
which provide the information to the JVM that class's
object which implement this is used as a thread.

while the collection interface doesn't provide any special
information to the JVM that's why it is not as a Marker
interface

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