James Roland 
How Transistors Work 

Did you know that electric current can be controlled? Have you ever wondered how that might be done? Transistors can act as amplifiers, taking in a small current and sending out a larger one, or as switches, turning electric current on and off. But how do these different transistors work? How are they used in our electronic devices? Discover the history of how transistors were developed, explore how different types of transistors can play different roles in electronics, and learn where transistors may be taking technology in the future!