A connected lightbulb can be turned on and off through a device that is also connected to the network or through commands that are sent to the bulb over bluetooth. If connected to your network, the lightbulb itself is setup like you would a computer or smart phone to grant it access to your home internet. Each bulb has a unique identifer so that commands to control the lightbulb can be sent to the right bulb.
Facts about smart lightbulbs.
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