ABSTRACT
This chapter defines what crowdsourcing is and what its main characteristics are based on a literature review. Specifically, it discusses its origins, its essential elements – crowdsourcer, platform, task, and participants – and other aspects related to these activities whose presentation facilitates the understanding of them. These are the scope and duration of the crowdsourcing projects, the incentives offered in exchange for participation, the ethics and privacy policies surrounding it, and the control mechanisms that can be implemented to favor its success.
