ELI5: Explain Like I'm 5

bjt transistors

BJT transistors are tiny switches that are used in electronic devices and machines. They are like tiny on/off switches. They allow electricity to flow through them and control how much electricity flows. You can think of them as tiny gates that open and close to let electricity go through them. They are very small, and because of this, they can be used in very tiny electronic circuits. So they allow us to make small and powerful electronic devices.