Networking: TCP vs UDP

The internet runs on these two protocols.

TCP (Transmission Control Protocol)

• Connection-oriented: "Hello? Are you there? Yes. Okay, here is data."
• Reliable: Resends lost packets. Checks order.
• Heavy: Handshakes, Acks.
• Use for: Web (HTTP), Email, Files.

UDP (User Datagram Protocol)

• Connection-less: Fire and forget. "Catch this!"
• Unreliable: If packets drop, too bad. No resend.
• Fast: No overhead.
• Use for: Video Streaming, Gaming, DNS.

The Analogy

TCP is a phone call. You verify the other person is listening. UDP is sending a letter. You drop it in the box and hope it arrives.

Conclusion

If accuracy matters (Bank transfer), use TCP. If speed matches (Headshot in CS:GO), use UDP.