Rensselaer Polytechnic Institute, or RPI, is a private research university located in Troy, New York. It was founded in 1824 by Stephen Van Rensselaer for the "application of science to the common purposes of life", and is the oldest technological university in the English-speaking world. Built on a hillside, RPI's 275-acre (111 ha) campus overlooks the historic city of Troy and the Hudson River and is a blend of traditional and modern architecture. The institute operates an on-campus business incubator and the 1,250-acre (510 ha) Rensselaer Technology Park, and is known for its success in the transfer of technology from the laboratory to the marketplace. RPI's mission has slowly evolved over the years while retaining a focus on the scientific and technological roots upon which it was founded. Over the past century, RPI has grown into a university with 5 schools: The School of Architecture, The School of Engineering, The School of Humanities, Arts, and Social Sciences, The School of Science, and the Lally School of Management & Technology. All together, the university offers around 140 degree programs in 60 fields leading to bachelor's, master's, and doctoral degrees.