So I watched a youtube documentary about future rockets and space travel etc and the narrator said if you were moving at 99% the speed of light, 1 day onboard the ship would be an entire year on earth. Now what I don't quite understand is the word time. Do they mean if someone on earth set their stop watch for 24 hours and someone on the ship set their stopwatch for 24 hours also, the stopwatch in the ship would move much much slower? Do they mean that the person in the ship ages slower or what? Lets just assume the ship was orbiting the earth ar 99% the speed of light and did so for 1 day and then landed again on earth, would everybody be 1 year older? As in 365 days have passed on earth but the persons stopwatch on the ship has only counted 24 hours? I'm not sure what they mean by the word time in this instance.