Is the possibility of resending data lost when using UDP and TCP protocols discussed?

The TCP protocol implements built-in mechanisms for retransmitting lost data — this is one of TCP's key features ensuring reliable delivery. If a packet is not acknowledged by the receiver, TCP automatically retransmits it.

In UDP, such a mechanism is absent: UDP is a connectionless protocol without delivery guarantees, so lost packets are not automatically recovered. If reliability is required, retransmission must be implemented at the application level.