RG6 is the industry standard 75 Ohm coaxial cable for TV and Satellite installations; it is a good all round general cable for most installations. Typically it is made up of a centre core comprising of pure copper or a copper clad steel, foam di-electric, foil shield, copper/aluminium braiding, then a PVC weatherproof outer core.
For professional installations, longer cables runs or situations where interference may be a problem we would always recommend the better quality CT100, featuring a pure copper core and pure copper braiding for increased interference tolerance and less signal loss.