On 16 December 1947, John Bardeen and Walter Brattain built and demonstrated at Bell Labs the first functional transistor: a point-contact device on germanium that amplified electrical signals without vacuum tubes. William Shockley, director of the semiconductor research team, was not present at the decisive experiment — he had been sidelined from the experimental work due to internal tensions with Bardeen — and responded by developing in 1948 the junction transistor, a more robust, scalable architecture that garnered much of the later credit. All three shared the Nobel Prize in Physics in 1956. The transistor is the most important platform shift in the history of technology: it replaces vacuum tubes — fragile, bulky, and power-hungry — with miniaturizable solid-state devices, paving the way for the integrated circuit, the microprocessor, and all modern digital hardware. It is estimated that more than 10²² transistors have been manufactured, making it the most-produced artifact in human history. The public narrative tended to concentrate credit on Shockley, who led the team and was more visible; Bardeen and Brattain are the experimenters who built and demonstrated the first functional device.