Current is the flow of electrical charges (usually electrons) in an electrical circuit. When you hook a lightbulb to a flashlight battery, the current flows from the negative terminal to the positive terminal, always in the same direction. This is called DIRECT CURRENT. Electrical current from a standard household outlet changes direction 60 times each second (50 times per second in Europe). Because the current flows first in one direction and then the other, this is called ALTERNATING CURRENT. The power company uses alternating current because it can be transformed to higher and lower voltages (with transformers) allowing them to transmit and distribute power with lower losses.
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