ABS (Acrylonitrile Butadiene Styrene) is a standard Engineering plastic used in car bumpers and helmets and other plastic household products. It is stronger than PLA, but not as flexible as PET filament.
Its cons are that it has a higher shrinkage rate than PLA (Around 8%. Can lead to prints curling or even splitting in extreme cases) a heated bed on your 3D printer can help make printing with ABS easier.
This special filament has a conductive element in it. You are able to make prints that can have printed circuit boards embedded inside them. The possibilities here are incredible.