Networking networking protocols

What is TCP?

Definition

TCP (Transmission Control Protocol) is a reliable, connection-oriented network protocol that ensures data arrives in order and without loss. It uses a three-way handshake to establish connections and acknowledgments to confirm delivery.

Why It Matters

TCP is the transport layer for HTTP, HTTPS, SSH, FTP, and most internet communication. Understanding TCP helps developers debug connection issues, optimize performance (keepalive, Nagle's algorithm), and choose between TCP and UDP for different use cases.

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