Context

Network communication choices affect latency, reliability, and application behavior. Interviewers ask this to test whether you understand transport-layer trade-offs and can connect them to real systems.

Core Question

Explain the differences between TCP and UDP. In your answer, address:

1. How each protocol handles connection setup, delivery guarantees, ordering, and retransmission.
2. Why TCP is typically used for reliable data transfer while UDP is preferred for low-latency communication.
3. Which kinds of applications are better suited for each protocol, and why.

Scope Guidance

You do not need to derive packet formats from memory, but you should be able to compare the protocols clearly, describe the main mechanisms behind reliability and speed, and discuss practical trade-offs such as overhead, congestion handling, and message loss.