In one of his recent posts Christoph Hochstrasser looks at socket programming done the right way, complete with code examples showing both client and server setups.
When writing about socket programming with PHP, nearly all articles are about the Socket Extension, despite it's the unfriendliest and most cumbersome way to work with Sockets in modern PHP. Let me introduce you to something, which apparently is pretty unknown among PHP programmers.
He starts off by introducing the concept of a socket (for those that are beginners on the topic) and talks about two of the major ways to work with them - the Socket extension and Streams. He shows how to use the stream_socket_client_* functions to connect to a remote server and make a HTTP request for the base page. He also shows the other side of things, making a simple "echo" server that binds to port 1337.