There are many standards (and recommendations) that make the Internet work. Networking standards such as IEEE 802.3 (Ethernet) and on top of them are the main protocols Internet Protocol (IPv4 and IPv6), Transmission Control Protocol (TCP, RFC793) and User Datagram Protocol (UDP, RFC768).
The remainder utilise these transport protocol to provide services such as the Domain Name Service (DNS), Web Sites (HTTP), Email (SMTP/POP/IMAP), Newsgroups (NNTP), File transfer (FTP), Telnet, SSH, ... the list is quite long.
Many of the "standards" are only recommendations and can be found at
http://www.faqs.org/rfcs/
(Requests For Comment)
For example, TCP is defined in RFC 793, and IPv4 is in RFC 791