Moving from a schematic diagram to real circuits. I have a few questions: Since the ammeter should be connected in series, why should the positive pole of a battery be connected to the ammeter's "positive" plug. Won't it be connected in parallel that way? If you didn't get what I mean see the first figure in this link: http://www.allaboutcircuits.com/vol_6/chpt_2/4.html (Follow the wires) And then another thing, we know that the resistor like the capacitor like the switch doesn't have a negative plug or a positive one.. Then how will I know how should I connect the appliance that follows if it has those "+ve -ve" PLUGS? I mean how should I know where to plug in the connection wire? I will be grateful for any descriptive answer, or link, or whatsoever.