Socket connections can be divided into three basic types, which reflect how the connection was initiated and what the local socket is connected to. These are

• Client connections.
• Listening connections.
• Server connections.

Once the connection to a client socket is completed, the server connection is indistinguishable from a client connection. Both end points have the same capabilities and receive the same types of events. Only the listening connection is fundamentally different, as it has only a single endpoint.