Discuss the unique characteristics of watercolor. what are the positive and negative features of watercolor? why would an artist select watercolor over other painting media?

Watercolor is know for its transperancy and fluidity.   It is the white of the paper glowing through the transparent paint that gives watercolor its luminosity. Opaque color blocks the light, preventing it from being reflected off the paper, resulting in colors that are somewhat duller in appearance.  Watercolor gives a brighter shinier color instead of a darker duller.  Watercolor has its negatives.  It is not the best quality paint and many professionals prefer to use darker opaque colors to make it look more real, not as childish.  

photography had emerged as an elite art pursued by a few creative individuals for a few wealthy patrons. but now, said bauldelaire, it was succumbing to "the great industrial madness of our times." it was becoming a mass production industry that catered to middle-class tastes, including a taste for gadgetry. the stereoscope, the first 3d imaging system, had turned looking at photographs into parlor entertainment. a "thousand hungry eyes were bending over the peepholes of the stereoscope as though they were the attic-windows of the infinite.