The spherical geometry that was discussed in the previous posts actually has a surprising number of real-world applications. For example, pilots and sailors use it all the time in their jobs to find the shortest path to their destination. Remember, that Earth has a spherical form and therefore the Euclidean rules of the plane applied to the surface of the planet won’t work like that.
So, the pilots, who deal with spherical geometry on a daily bases, have to go through mathematical calculations discussed here, along with other more complex derivations, every time they want to analyze the direction or the path of their journey. A perfect career choice for people who want to do math all day long.