 0. The task is outsourced through an open call from the employer; 0. The recipients of the call, whether or not they elect to participate, comprise a large, amorphous crowd. The following discussion of crowdsourcing reflects our understanding of three of the most significant types of crowdsourcing: microtasks, "professional" tasks, and "game" tasks. Microtasks facilitated by platforms such as Amazon Mechanical Turk [