Determining Resistance Value for LED

How to find the resistance (resistor value) needed for a particular LED (Light Emitting Diode) usig Ohm's Law R = V/I: Resistance = voltage / current. In this case, it's a voltage difference (delta voltage) R = (SourceVoltage - LEDVoltageRating)/I. In the video, the 2 volts is the voltage of the LED and the .01 amps, or 1 miliamp is the amp rating of the LED.