Erlang Interface

Erlang communicates with external programs through objects called ports. If we send a message to a port, the message will be sent to the external program connected to the port. Messages from the external program will appear as Erlang messages that come from the ports.

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Note the difference between using a port to communicate with an external process and a socket. If you use a port, the port will behave like an Erlang process, so you can link to it, send messages to it from a remote distributed Erlang node, and so on. If you use a socket, it will not behave like a process. (Armstrong 2013, 232)