When we think of crowd sourcing, we often think about Wikipedia or Youtube, but Amazon's Mechanical Turk is a different type of crowd sourcing.
Mechanical Turk is an online marketplace where employers can hire thousands of workers to complete tiny tasks such as identifying objects in a photo or editing a description. Workers are offered no benefits and are not protected by minimum wage laws. They are paid per task, often as little as 20 cents, occasionally as much as $5. But sometimes, they aren’t paid at all.