Coaxial cable, and single-mode vs multimode fiber (distance, light source, core size)

Coaxial (coax) cable has a solid copper center conductor, surrounded by insulation, a braided or foil shield and an outer jacket. The shared axis gives it its name, and the shield makes it quite resistant to interference. Today you will mainly see coax delivering cable TV and cable internet, connecting the provider's line to a cable modem, and in some security camera and antenna installations. RG-6 is the common type for cable TV and internet, while RG-59 is thinner and older. Early Ethernet also used coax, but modern LANs do not.