Why is TCP preferred over UDP for applications requiring extensive error checking (for example, HTTPS)?

TCP is preferred for applications like HTTPS because it provides reliable, ordered, and error-checked delivery of data. A key mechanism for this reliability is TCP's use of acknowledgments (ACKs). When a TCP segment is received, the receiver sends an ACK back to the sender, confirming receipt. If an ACK is not received within a certain time, the sender retransmits the segment. UDP, in contrast, is a connectionless protocol that operates without acknowledgments, making it faster but unreliable. Therefore, UDP does not guarantee delivery, order, or error checking, which are critical for applications like HTTPS where data integrity is paramount.