The computer scientist Jaron Lanier popularised the term virtual reality in the early 1980s to describe a technology that enables a person to interact with a computer-simulated environment, be it based on a real or an imagined place. Virtual reality environments are usually visual experiences, displayed on computer screens or through special stereoscopic displays. Some simulations include additional sensory information such as sound through speakers or headphones. Explorations into virtual reality by artists began in a relatively modest way; in 2002 the duo Langlands and Bell created a virtual reality tour of Osama Bin Laden's hideout in Afghanistan and audiences were invited to navigate the building using a joystick. With the introduction of Second Life on the internet, artists are now installing galleries and staging virtual exhibitions in the alternative virtual world. The Dutch team Art Tower stage exhibitions and sell art in Second Life and Cao Fei, who represented China at the 2007 Venice Biennale reproduced her exhibition in the Chinese pavilion in Second Life.