A: Lexington, Massachusetts, United States
In 1959 Wesley A. Clark designed and built the TX-2 computer at MIT’s Lincoln Laboratory in Lexington, Massachusetts. It had 320 kilobytes of fast memory, about twice the capacity of the biggest commercial machines. Other features were magnetic tape storage, an online typewriter, the first Xerox printer, paper tape for program input, and a nine inch CRT screen. Among its applications were development of interactive graphics and research on human-computer interaction.