From Apple to Facebook, Silicon Valley’s freewheeling ecosystem of new, nimble corporations created massive wealth and retilted the world’s economic axis." The tech giants began as small engineering-focused firms building new products when their larger competitors were less innovative (such as Xerox when Apple was founded in 1976). The companies engaged in timely investment in rising technologies of the personal computer era, dotcom era, e-commerce, rise of mobile devices, social media, and cloud computing.