The speed of light in a vacuum is a fundamental constant of nature, denoted by the letter c, and its value is approximately 299,792,458 meters per second (m/s).

Here are some important points:

* Constant: The speed of light in a vacuum is always the same, regardless of the speed of the source or the observer.

* Maximum: No object with mass can travel at or faster than the speed of light.

* Varying in mediums: Light travels slower in materials like water or glass compared to a vacuum.

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