Alan Curtis Kay (born May 17, 1940) is an American computer scientist best known for his pioneering work on object-oriented programming and windowing graphical user interface (GUI) design. At Xerox PARC he led the design and development of the first modern windowed computer desktop interface. There he also led the development of the influential object-oriented programming language Smalltalk, both personally designing most of the early versions of the language and coining the term "object-oriented."
He has been elected a Fellow of the American Academy of Arts and Sciences, the National Academy of Engineering, and the Royal Society of Arts. He received the Turing award in 2003.Kay is also a former professional jazz guitarist, composer, and theatrical designer. He also is an amateur classical pipe organist.