awg is the gauge of the cable i think. I've just bought a load for my rib from
www.sea-screw.com. AWG 16 is about 1.5mm^2 end on wire area whereas AWG 8 is about 8mm^2 (so smaller the AWG rating the thicker the cable).
I'm using AWG 16 for all connection bits and AWG 8 for my main feed from the battery.
Hope that helps a bit. I can recommend sea screw as they were very helpful and had quick delivery.