How do transistors work?

Transistors are electronic components that act as switches, amplifiers or current regulators. They consist of three layers of semiconductor material: p-type (positively charged), n-type (negatively charged), and a thin layer in between called the depletion region. When a voltage is applied to the transistor's base (the middle layer), it creates an electrical field that allows current to flow from the emitter (the N-type layer) to the collector (the P-type layer). This creates an amplification effect that can be used to switch on or off larger currents or to amplify small signals. Transistors revolutionized electronics by replacing bulky vacuum tubes and making small, portable devices possible. They are now used in everything from computers and smartphones to cars and medical equipment.