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It is possible to construct circuits with two or more bulbs. Here is one example. The

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two bulbs in this circuit are connected in parallel. If we follow two electrons traveling

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through this circuit, we see there are two possible paths. One electron leaves the negative

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terminal of the battery and travels through the upper bulb, the other through the lower

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bulb. They both end at the positive terminal of the battery. Parallel circuits always provide

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more than one path for the electricity to travel on. If you are in a room with a

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row of ceiling lights, these lights will be connected in parallel. One advantage

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of connecting lights in parallel is that if one light is removed or fails, the

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other lights will not be affected. Removing one light from this circuit

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does not affect the other light. It remains connected to the battery. This is

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parallel circuit notice when I disconnect one bulb the other one stays

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on it is possible to build parallel circuits with many branches this circuit

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also has two bulbs but notice there is only one path this is a series circuit

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all electrons travel from minus to plus following the same path if one of these

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lights is removed or fails the circuit is broken and the other light will go

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out. Lighting systems are rarely wired in series. This is a series circuit. Notice

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when I disconnect one bulb the other one goes out. Switches are wired in series

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with the loads they control. In this example our lights are the loads and

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this circuit contains a series and parallel component. The switch is in

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series with the parallel branches. This is how one switch controls many lights

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in a room. Series and parallel circuits can be found in all electrical and electronic devices.

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The wiring in your home is a combination of series and parallel circuits.