PING uses a telephone menu system to distribute active commands to participants who call in using cellular telephones. The choices made by the caller when navigating the telephone system produce directions for physical movement through the city.PING comes out of psychogeographical inquiry, which focuses on the study of the effects of the environment on the perception, behaviour and mood of individuals. PING is intended to explore the interface between disparate fields such as situationist thought that focuses on subjective mood, generative psychogeography which introduces algorithms as a way to inspire movement through urban space, existentialism, and the interpolation of digital metaphors onto physical, analog space.(Source: Author's description from project site)