Port   A port is both a connectable element and a structural feature of an encapsulated classifier. A port specifies the way a classifier interacts with its external environment or the way the internal environment of the classifier provides services to its external environment. A port may be connected directly to other elements in its external environment but typically uses interfaces to declare either the services that it provides or the services that it requires. A port can be connected to the internal environment of the classifier by connectors. The connectors forward incoming requests to elements in the internal environment or outgoing requests to the ports.

Explanation

A port is a mechanism for specifying how a classifier interacts with its environment and can be used to make a classifier a replaceable part of a model. A port may specify either the services that a classifier provides to its environment or the services that it requires from its environment. It is a point of interaction between the internal environment of a classifier and its external environment.