I blogged an introduction to and explanation of SPDY, the next-gen HTTP. It should cover all the basics.
SPDY (pronounced speedy) is a replacement for HTTP, and feels like a wrapper for it. SPDY is a packet (frame) oriented binary protocol, usually wrapped in TLS (SSL), and as such a little harder to follow than HTTP. Our care free days in the jungle, surviving on the bare necessities and debugging connections with telnet, are coming to an end. In exchange, we get faster loading apps, which are secure by default.
The most important goal of SPDY is to transport web content using fewer TCP connections. It does this by multiplexing large numbers of transactions onto one TLS connection.
What is SPDY? – Read the rest