A send port is the combination of a send pipeline and a send adapter. A send port group is a collection of send ports and works much like an e-mail distribution list. A message sent to a send port group will be sent to all send ports in that group. The send pipeline is used to prepare a message coming from BizTalk Server for transmission to another service. The send adapter is responsible for actually sending the message using a specific protocol such as SOAP, or FTP.