Other defense contractors sprouted nearby during the 1950s. The Lockheed Missiles and Space Division, which built submarine-launched ballistic missiles, was founded in 1956 next to the NASA Center; by the time Jobs moved to the area four years later, it employed 20,000 people. A few hundred yards away, Westinghouse built facilities that produced tubes and electrical transformers for the missile systems. "You had all these military companies on the cutting edge," he recalled. "It was mysterious and high-tech and made living here very exciting." In the wake of the defense industries there arose a booming economy based on technology. Its roots stretched back to 1938, when David Packard and his new wife moved into a house in Palo Alto that had a shed where his friend Bill Hewlett was soon ensconced. The house had a garage, an appendage that would prove both useful and iconic in the valley, in which they tinkered around until they had their first product, an audio oscillator. By the 1950s, Hewlett-Packard was a fast-growing company making technical instruments.