Coaxial Cable - This consists of a solid copper core surrounded by insulation which is then surrounded by a copper shielding and finally covered with a plastic sheath. Coaxial cable is widely used for television wiring as it has enough bandwidth to handle a television signal over a typical run from antenna to television.
Early computer networks also used coaxial cable with a bandwidth of 10Mbps. But for high speed networks (100 Mbps and above) coax cable is no longer sufficient


Twisted Pair Cable - There are 8 colour-coded wires with each related pair twisted around one another. Twisting it in this way reduces signal loss over any given length of cable.
Twisted pair cable is widely used in 100 Mbps and 1 Gbps networks. In order to guarantee the performance of the cable.


Fibre Optics - fibre optic cable works by a light signal being 'launched' at one end of the glass thread core. The light is reflected internally down the fibre until it reaches the other end. Light sensitive electronics then pick up the signal.
The downside of fibre is the cost - it is more expensive that ordinary UTP network cable therefore it is only cost-effective if there is a very high bandwidth requirement or if the network has very long cable runs.
If fibre-optic could be laid from the telephone exchange right up to the house then broadband bandwidth of 100 Mbps is quite possible. At the moment fibre-to-cabinet is the norm in the UK, where it is fibre from the exchange to the nearest junction box, then normal copper cable to the home.


Wireless signal - Connection between computer and router is achieved using radio waves.
This has the strong advantage of not requiring cables to be laid through a building. On the other hand radio is very prone to being weakened by walls and other objects.
The bandwidth of a wireless network is lower than a physical network.