FTP; HTTP; DNS (uses both TCP and UDP); several e-mail protocols including POP3, SMTP, IMAP4.
TCP
TCP
That would render most protocols useless. TCP provides the reliability that is required for many applications.
It does. see the tcp video tutorials
list 2 major types of internet application and their use
UDP
HTTP works over a TCP connection.HTTP works over a TCP connection.HTTP works over a TCP connection.HTTP works over a TCP connection.
UDP
You should use "netstat":netstat -p TCP
Aknowlagement
Yes, it does.
No, TCP/IP is the not the only protocol used in the world, but it is certainly one of the most popular. Older networks may still use IPX/SPX (Novell) which is a competitor to TCP/IP. Mainframes use SNA or LU6.2 protocols which are very different from TCP/IP. Appletalk is also a competitor to TCP/IP.