This is a device used by a computer to access the network. It is modeled as a port that is placed on the network node (Server, etc).
IP
This is a Network Adapter that uses the TCP/IP protocol. It's name is given the IP address.
Port
This is a TCP/IP port that an application or service "listens on." The name is given the port number.
Example Diagram
The following diagram shows a PC and two Servers connected via TCP/IP. The internal components listen on the specified ports and the computers communicate with other computers via their IP network adapters.