Light itself doesn't carry information. It's the way we manipulate this light that allows us to communicate. Communication technologies encode information onto the light wave. There are two main methods: Amplitude Modulation (AM): This method varies the intensity (amplitude) of the light wave to represent information. Imagine a flickering light bulb - a bright flash could represent a 1, while a dim flicker could represent a 0. This method is used in some older radio transmissions. Frequency Modulation (FM): Here, the frequency (number of cycles per second) of the light wave is varied to represent information. Think of a police siren - a high-pitched whine could represent a 1, while a lower-pitched wail could represent a 0. FM is more resistant to interference and is used in many modern radio transmissions.
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