"shades" is a very informal way of saying sunglasses.
In Australia Shades are like curtains (Different material).
Sunglassesand Aviators KeyDifference:Sunglassesrefer to eye wearglassesthat block the harmful sun rays from reaching to the eyes directly and also guard the eyes from bright light. Aviators are specific types ofsunglassesoriginally branded as a Ray Ban product.
Shades are a totally different thing??
It depends on how cool, or inversely how pretentious, the person wearing them is.