Common Ethernet network cables are straight and crossover cables, which are made of 4 pairs of twisted copper wires in a cable jacket. Straight cables have the same wire color arrangement on both ends and are used to connect devices like computers to switches or routers. Crossover cables have a different wire color arrangement on each end and are used to connect like devices such as two computers or two switches. The document provides details on identifying and making straight and crossover cables by crimping RJ45 connectors onto the cable ends according to the standard 568B wiring color scheme.