Despite of its age, Beej's Guide is still one of the best introductions to network programming I've seen so far. I love how apart from the basic and concise exp

Despite of its age, Beej's Guide is still one of the best introductions to network programming I've seen so far. I love how apart from the basic and concise explanation of TCP and UDP (and generally sockets in UNIX-like environments), there's also a separate, short "Advanced Techniques" section that can be very useful if you want to explore the subject even further.