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A slide is
A conductor is...
Electric energy = charge $\cdot$ voltage
Charge measured in Coulombs, voltage measured in Volts
Current is moving charge.
Measured in Amps: 1 Amp = 1 Coulomb / sec
Electric current will take the path of lowest resistance to get from high voltage to low voltage.
Usually that means *anything but air*. Voltages have to get *very high* before air will become a conductor.
If the voltage difference between two places is constant (like a battery) $\Rightarrow$ constant current (direct current).
If the voltage difference between two places is changing (like a wall socket) $\Rightarrow$ varying current (alternating current).