The Exposure Triangle comprises aperture, shutter speed, and ISO. These three camera and lens controls work together to regulate the amount of light that makes it to the light-sensitive surface (aperture and shutter speed) and the sensitivity of that surface (film or digital ISO).
What Sells Best On Shutterstock?
Some types of photos that sell best are Portrait Photography, Food Photography, Landscapes (usually with people) and fine art photography (artsy).