This article describes the history of the birth of timelines and the development of some variants, and introduces the concept that time is not a “merely sequence”. This is similar to what I have read about the perception and description of time in the literature before. This article focuses on the timeline itself and its history, but does not describe and analyze much about the shape of modern timelines. This reminds me of the movie Arrival and Tenet in their related scenes. Suppose there is a plane and there is a worm on the plane, it can only crawl forward one kilometer after it is born in the plane before it dies, it can choose from an infinite number of paths, each different path does not overlap, for the worm, the path not taken ahead is unknown, the other paths not taken are also unknown, then for the worm each path is linear. Then the observer, appear, and you see all the paths of the worm on this plane in a higher dimension and all the corresponding endpoints of the paths. Then the bug will follow the observer’s navigation route to crawl forward, and foresee what things will be encountered in this path. We are like the observer when we are drawing or analyzing a timeline, because we have the knowledge of what happened. For the observer, time is non-linear and they can see in a higher dimension every human choice and the different results of different choices.