User-generated content refers to various types of media created by users and shared online. There are both implicit and explicit incentives for users to generate content. Implicit incentives include social motivations like feeling like an active member of a community and connecting with other users. Explicit incentives are more tangible rewards provided by sites, such as points, badges, privileges or monetary compensation, to encourage user participation in generating content. Understanding what motivates users is important for designing sites that facilitate user-generated content.