There are big banners everywhere. At Times Square they are huge LED screens that might even be HD. At other places, we see mostly vinyl or paper based banners that are glued to the space… Do you remember a time when those banners were actually painted on the walls… by real people.
Here is a short documentary that I have seen at Wooster Collective. A great piece, which explains and shows in detail how and by who those banners were painted in huge scales on the walls of big cities.