TCP
Formal definition:
TCP is an abbreviation for Transmission Control Protocol. It’s a protocol on the transport layer used while transporting data through the Internet.The TCP service model includes a connection-oriented service and a reliable data transfer service. TCP also includes a congestion-control mechanism, a service for the general welfare of the Internet rather than for the direct benefit of the communicating processes.[1]
Informal definition:
When you want to send some files, such as pictures, you can do it according to some protocol, or others cannot receive your data. The protocol is written by an organization named IEEE and obeyed by all the users using transport service. If you do thing according the TCP, you can transport your data to anywhere around the Internet, and it’s guaranteed that others receive your data without any loss. TCP also include a congestion-control mechanism. It will help improve the fluency of the Internet like a traffic policeman direct the traffic to prevent traffic jams.
[1]James F. Kurose, Keith W. Ross, Computer Network: A Top-Down Approach 5th edition, 2010
meng91 