There are so many different networking protocols out there...it's incredible.
Some examples:
CLNP Connectionless Networking Protocol
EGP Exterior Gateway Protocol
EIGRP Enhanced Interior Gateway Routing Protocol
ICMP Internet Control Message Protocol
IGMP Internet Group Management Protocol
IGRP Interior Gateway Routing Protocol
IPv4 Internet Protocol version 4
IPv6 Internet Protocol version 6
IPSec Internet Protocol Security
IPX Internetwork Packet Exchange
Routed-SMLT
SCCP Signalling Connection Control Part
AppleTalk DDP
ADC, A peer-to-peer file sharing protocol
AFP, Apple Filing Protocol
BACnet, Building Automation and Control Network protocol
BitTorrent, A peer-to-peer file sharing protocol
BOOTP, Bootstrap Protocol
CAMEL, an SS7 protocol tool for the home operator
Diameter, an authentication, authorization and accounting protocol
DICOM includes a network protocol definition
DICT, Dictionary protocol
DNS, Domain Name System
DSM-CC Digital Storage Media Command and Control
DHCP, Dynamic Host Configuration Protocol
ED2K, A peer-to-peer file sharing protocol
FTP, File Transfer Protocol
Finger, which gives user profile information
Gnutella, a peer-to-peer file-swapping protocol
Gopher, a hierarchical hyperlinkable protocol
HTTP, Hypertext Transfer Protocol
IMAP, Internet Message Access Protocol
Internet Relay Chat (IRC)
ISUP, ISDN User Part
LDAP Lightweight Directory Access Protocol
MIME, Multipurpose Internet Mail Extensions
MSNP, Microsoft Notification Protocol (used by Windows Live Messenger)
MAP, Mobile Application Part
NetBIOS, File Sharing and Name Resolution protocol - the basis of file sharing with Windows.
NNTP, Network News Transfer Protocol
NTP, Network Time Protocol
NTCIP, National Transportation Communications for Intelligent Transportation System Protocol
POP3 Post Office Protocol Version 3
RADIUS, an authentication, authorization and accounting protocol
RDP, Remote Desktop Protocol
Rlogin, a UNIX remote login protocol
rsync, a file transfer protocol for backups, copying and mirroring
RTP, Real-time Transport Protocol
RTSP, Real-time Transport Streaming Protocol
SSH, Secure Shell
SISNAPI, Siebel Internet Session Network API
SIP, Session Initiation Protocol, a signaling protocol
SMTP, Simple Mail Transfer Protocol
SNMP, Simple Network Management Protocol
SOAP, Simple Object Access Protocol
STUN, Session Traversal Utilities for NAT
TUP, Telephone User Part
Telnet, a remote terminal access protocol
TCAP, Transaction Capabilities Application Part
TFTP, Trivial File Transfer Protocol, a simple file transfer protocol
WebDAV, Web Distributed Authoring and Versioning
XMPP, an instant-messaging protocol
For a full list check out the Wikipedia article....