A coaxial cable is a type of electrical wire and signal transmission line, typically constructed from four layers of material: at the very center lies a conductive copper wire; surrounding this wire is a layer of plastic (serving as an insulator or dielectric); outside the insulator is a thin, mesh-like conductive layer (typically made of copper or an alloy); and finally, enclosing the conductive layer is the outermost insulating material, which serves as the protective jacket.
Coaxial cables can be used for the transmission of both analog and digital signals and are suitable for a wide variety of applications. Among the most significant of these are cable television broadcasting, long-distance telephony, short-range connections between computer systems, and Local Area Networks (LANs). Coaxial cable has seen rapid development as a means of delivering television signals to households-a technology known as cable television. A single cable television system is capable of carrying dozens, or even hundreds, of TV channels, with a transmission range that can extend for tens of kilometers. For a long time, coaxial cables have served as a vital component of long-distance telephone networks.
