Let’s Get Technical
Do you know how the warp engines work? Particles of matter and antimatter commingle in a reaction chamber regulated by a dilithium crystal. What happens then is the particles interact, which destroy each other, giving off enough energy to allow the spaceship to warp into space.
Source: National Geographic News
The Enterprise can operate safely from warp drive 1 to 9.2. In Star Trek: Voyager, traveling at warp 10 mutates humans into big salamander creatures. But then in the final episode of TNG, “All Good Things,” Federation starships traveled at warp 13.