Solid-State Electronics Transform Computing
The invention of the transistor at Bell Laboratories in 1947 by John Bardeen, Walter Brattain, and William Shockley ranks among the most consequential technological breakthroughs of the twentieth century. A transistor performs the same switching function as a vacuum tube but does so using solid-state semiconductor materials, primarily silicon, rather than heated filaments in glass enclosures. This fundamental change in the underlying physics of electronic switching brought dramatic improvements in every dimension that mattered for computing: transistors were smaller, faster, more reliable, consumed far less power, generated far less heat, and could be manufactured at much lower cost than vacuum tubes.
The transition from vacuum tube computers to transistorized computers occurred throughout the late 1950s and 1960s, a period often referred to as the second generation of computing. Machines like the IBM 7090, introduced in 1959, and the CDC 1604, designed by Seymour Cray, demonstrated that transistor-based computers could deliver vastly superior performance while occupying a fraction of the space required by their vacuum tube predecessors. The IBM 7090 was roughly six times faster than its vacuum tube predecessor the IBM 709, consumed significantly less power, and required far less maintenance. These improvements made computers practical for a wider range of organizations, moving them from the exclusive domain of military and research institutions into universities and large corporations.
The transistor era also saw the emergence of the commercial computer industry as a major economic force. IBM established its dominance with the System/360 family of mainframes, which introduced the revolutionary concept of a compatible family of computers spanning different performance levels, allowing organizations to upgrade without rewriting their software. Digital Equipment Corporation disrupted the market from below with the PDP series of minicomputers, bringing interactive computing to smaller organizations and research labs at a fraction of mainframe prices. The programming landscape evolved in parallel, with the development of high-level languages like FORTRAN and COBOL and the first operating systems that could manage multiple programs running concurrently. However, even as transistorized computers transformed the industry, engineers were already pursuing the next revolution: combining multiple transistors onto a single piece of semiconductor material.