Second Life is a 3D virtual world created and owned by its users, known as Residents. Residents interact through customizable avatars and can socialize, participate in individual and group activities, and interact with other Residents and applications. The virtual world is used for a variety of purposes including education, business, and social networking. Residents can earn the virtual currency of Linden dollars through various jobs, activities, and businesses within Second Life. Many universities, companies, and organizations have a presence in Second Life for activities like virtual classes, meetings, simulations, and recruiting.