Transmission Control Protocol and User Datagram Protocol are two transport layer protocols that are widely used with Internet Protocol. A protocol is a set of procedures and rules that two computers follow to understand each other and exchange data. Although TCP is the most widely used protocol of the two, UDP is more useful in some situations.

Both protocols send data over the Internet in packets. Of the two, TCP is connection-oriented. After a connection is made, data travels bidirectionally. UDP is a simpler protocol that is connectionless.

TCP is more robust than UDP. It provides error correction features and high reliability. UDP is faster than TCP mainly because it does not provide error correction. Moreover, TCP handles flow control, while UDP does not have any flow control option.

TCP guarantees delivery of data to the recipient. If data is lost, TCP takes steps to recover the lost data and retransmit it. To do this, TCP tracks packets of data and checks the packets for errors.