Complex sentence: The Transmission Control Protocol (TCP) is one of the two original core protocols of the Internet protocol suite (IP), and is so ubiquitous that the entire suite is often called "TCP/IP".
Split into simpler sentences: The Transmission Control Protocol (TCP) is one of the core protocols of the Internet protocol suite. TCP is one of the two original components of the suite, complementing the Internet Protocol (IP), and therefore the entire suite is commonly referred to as "TCP/IP".