Web

OSI, TCP/IP

These three pages are so far the best to simply understand OSI, TCP/IP.

http://www.hardwaresecrets.com/the-osi-reference-model-for-network-protocols/

http://www.hardwaresecrets.com/how-tcp-ip-protocol-works-part-1/

http://www.hardwaresecrets.com/how-tcp-ip-protocol-works-part-2/

What really happens when you navigate to a URL

HTML tutorial

http://www.tutorialspoint.com/html/html_overview.htm