Yes, and they frequently do, although on different port numbers for different protocols.
UDP does not require as much resources as TCP but in the same time, it does not insure delivery of packets.
UDP is alot faster than TCP. So if its realtime obviously it has to be fast, thus UDP. The only problem is UDP isn't as reliable or as secure as TCP. But it does have the speed advantage.
UDP
UDP and TCP both are transport layer protocols. UDP is connection less and TCP is connection oriented. UDP is preferred over TCP when large amount data is to be sent like on skype or video conferencing .
TCP
TCP and UDP are two different layer 4 protocols. TCP reliably sends data with acknowledgments and UDP sends data without checking if the destination received it. Skype uses UDP while email uses TCP.
In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.In the commonly used TCP/IP communications, that would either be a TCP header, or a UDP header.
TCP is being used at the time being. UDP Support is still being developed in flash.
It depends on whether you want speed (UDP) or reliability (TCP).
Transport layer TCP/IP Protocols are TCP and UDP
the main difference between UDP and TCP is that UDP is not a reliable protocol.
transport