A message destination is a container for stored data, and can follow either the JMS topic or queue model.
A topic is a message destination that conforms to the publish-and-subscribe messaging paradigm
A queue is a message destination that conforms to the point-to-point messaging paradigm
Each message destination has at least two JMS Clients associated with it: a producer client at its input, and a consumer client at (each) output. JMS message destinations are discussed in Developing Java CAPS Projects.