Something that moves faster than a light turning on. or 299 792 458 m / s and as the person put above in the coments
"The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its precise value is 299792458 metres per second (approximately 3.00×10⁸ m/s), since the length of the metre is defined from this constant and the international standard for time"
so give a tnx to whosfrostyy