1) three types of inductors in electrical circuits?
2) TWO application of the capacitor in a simple transistor amplifier circuit?

How do electrical circuits make stuff work? Like i don't see how inducing a current on anythign can make it work… such as, how does an Xbox controller make the commands do stuff in game… things like that, idk i hope i conveyed my question well enough, but i am terribly confused

I am wondering how electrical circuits and systems are actually designed in the real world. Is there a formal process that goes into designing a circuit for a particular purpose? I have heard of electronic design automation for digital circuits, but how is this actually done? What about for analog circuits? Power systems? Thanks!
Thanks. I did have two other questions.

1.) Are there any particular tools that are necessary in any of the areas I specified?

2.) Is it possible to automate portions of the design process?

3.) Is there a really good tutorial available for this?

Hi,
I have 2 D-cell batteries. How many V and A does it produce?
I have a circuit (from a robot toy) that looks something like this:
http://aug18.imghost.us/7xVa.jpg (the one in the box labeled A).
The circuit can switch between the three states (as can be seen in boxes labeled A,B and C). The circuit is powered by 2 D-cell batteries and powers a simple motor.
What I want to do now is: I have 2 wires, each are either off or on. When they are on, they produce 5V and 40mA each. I want to modify the switches (labeled in X,Y,Z) and the switches only that when one of the wire is on and the other is off, the circuit becomes in the B-state and if one of the wire is off and the other is on, the circuit becomes the C-state. And when both wires are off or both of them are on, the circuit becomes the A-state. How do I do this and what do I need to do this? What components do I need? Im really bad at calculating and designing electrical circuits.
Can anyone help?
Thanks!