What are Sockets?
Sockets are just like "worm holes" in science fiction. When things go
into one end, they (should) come out of the other. Different kinds of
sockets have different properties. Sockets are either connection-
oriented or connectionless. Connection-oriented sockets allow for
data to flow back and forth as needed, while connectionless sockets
(also known as datagram sockets) allow only one message at a time to
be transmitted, without an open connection. There are also different
socket families. The two most common are AF_INET for internet
connections, and AF_UNIX for unix IPC (interprocess communication).
As stated earlier, this FAQ deals only with AF_INET sockets.