What are the differences between TCP and UDP? Why is UDP used for streaming video and voice?

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are transport protocols that operate over IP but have different characteristics.

Differences:

• TCP: connection-oriented, provides reliable data delivery, error checking, packet order, and retransmission of lost data. Uses connection establishment (handshake).
• UDP: connectionless, does not guarantee delivery, order, or data integrity. Faster and lighter in load.

Why is UDP used for streaming video and voice?

• In streaming video and voice, minimal delay and continuous transmission are important.
• Losing some packets is not critical — it's better to skip a frame or sound than to wait for retransmission and create delays.
• UDP allows faster data transmission without the overhead of acknowledgments and retransmissions.

Thus, UDP is suitable for applications where speed and low latency are important, rather than absolute delivery reliability.