
The transistor replaced bulky, fragile vacuum tubes with tiny, reliable electronic switches. That technical improvement may sound modest, but it is one of the foundational reasons the modern world fits in your pocket. Radios, computers, satellites, and smartphones all depend on the transistor's ability to control electrical signals efficiently.
Because transistors could be miniaturized and mass-produced, they opened the door to integrated circuits and modern computing. If the steam engine powered the industrial age, the transistor powered the digital one.
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