What is the primary difference between TCP and UDP?

The primary difference between TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) lies in the way they handle data transmission. TCP is a connection-oriented protocol, meaning it establishes a connection between the sender and the receiver before data can be sent. One of the key features of TCP is that it checks the integrity of data packets and ensures they are delivered in the correct order. This is achieved through mechanisms such as sequencing and acknowledgments, which allow the protocol to track which packets have been received and request retransmission of any that are lost or received out of order.

This reliability makes TCP suitable for applications where accurate data delivery is critical, such as web browsing, file transfers, and email. In contrast, UDP is a connectionless protocol that does not guarantee the order or reliability of message delivery; it simply sends packets without establishing a connection or ensuring they arrive in the correct order. This lack of overhead makes UDP faster and more efficient for applications that can tolerate some data loss, such as video streaming or online games.