FTL is short for Faster Than Light. Altough it is impossible to technically move faster than the speed of light through spacetime, those relativistic constraints do not apply to spacetime itself, making warp drive and wormholes theoretically possible. This is a form of BTC travel that is particularily practical for interstellar travel. Another possibility is photon-protected superposition which exploits the possibility in quantum physics to be in more than one place at a time!