One argument of why, is that if you could travel faster than light, then you could send a message to a point in Spacetime that is spacelike-separated from the present. But then since the target is spacelike separated, there exists a inertial frame of reference in which that event happens before the present, which would be hard to make sense of.
Faster-than-light (FTL) refers to the hypothetical ability to travel or transmit information faster than the speed of light in a vacuum, which is approximately 299,792 kilometers per second (about 186,282 miles per second). In the realm of physics, particularly according to Einstein's theory of relativity, nothing with mass can travel at or exceed the speed of light.
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