What is Resistance (R)?

To create resistance you need two forces pushing against each other. Lightbulbs have to resist the current to create light so when the electrons are going through a circuit to the lightbulb resistance stops some of the electrons which will make the lightbulb (wire) heat up and create light.

Think of resistance like this: you are pulling a pumpkin in a wagon. As you go up a hill there becomes some resistance when you pull. It becomes more difficult to pull the weight up the hill. When things like these become more difficult it is because two forces are pushing against each other.The same thing happens inside the circuit, the only difference is that as the two forces in the circuit push against each other there becomes heat in the wire and the lightbulb starts to glow or light up.

What is an incandescent lightbulb?

An incandescent lightbulb is when the electrons on the bulb go through the wire and resistance agitates the electrons creating light.