This document discusses different types of network cables used in communication systems. It describes three major types: coaxial cable, which has an inner conductor surrounded by insulation and a metal shield; twisted pair cable, made of two insulated wires twisted together; and fiber optic cable. It provides details on coaxial cable standards like RG-6 and RG-8, and describes single-core and multi-core coaxial cables. Twisted pair cable can be shielded (STP) or unshielded (UTP), and UTP is commonly used in computers and telecommunications. The document lists various online references for further information.