Answer by Egirl Team
That is a question that can’t be answered in just a few lines. There is quite a lot to it. If you are really interested in the subject you might consider studying online. Here is one resource that might get you started: http://www.electronicstheory.com/COURSES/ELECTRONICS/e101-1.htm
Registration for the Society of Women Engineers' 2016 Invent It Build It program in Philadelphia, PA is open now. This is a hands-on engineering event, for middle and high school girls with an informational program for parents and educators Be sure to go to the SWE website to sign up and reserve your space!
IIBI Registration on the SWE website