Special Relativity is a theory developed by Albert Einstein in 1905, and seeks to explain how space, time, and motion all behave when an object is moving extremely fast; approaching the speed of light, and that nothing can move faster than light (which is the only constant of this system). Also, and perhaps most importantly, all measurements of space and time were considered from the speed and position of the observer. Einstein’s system is considered universal, whereas Newton’s, which only takes these considerations from the perspective of being on Earth, is not. To note, Einstein came up with a theory on General Relativity, of which Special Relativity is a part.
One of the concepts of Special Relativity is time dilation, which shows that time moves more slowly for objects traveling at higher speeds compared to those that are standing still. The videos explain this by emphasizing that the speed of light is measured the same, independent of the observer, and that it is time and distance which are variable instead. One application of this is our research into space travel. While we do not currently have the technology to allow us to travel fast enough to see dramatic effects of time dilation, in theory, astronauts traveling nearer the speed of light should age more slowly than people back on Earth, as seen in the film Interstellar. Perhaps a more realized application of time dilation is evidenced in our use of global positioning system. As GPS satellites orbit Earth at very high speeds, they may experience time slightly differently compared to clocks here, which need to be corrected for in order to prevent errors in navigation.