Sure! It's pretty straightforward actually. The first approach (which is a simplification) uses the usual way to calculate a distance between two points on a F

Sure! It's pretty straightforward actually. The first approach (which is a simplification) uses the usual way to calculate a distance between two points on a FLAT plane, which using is the Pythagorean Theorem. So d = √((y1 - y2)^2 + (x1 - x2)^2). The second approach uses the haversine formula: https://en.wikipedia.org/wiki/Haversine_formula https://en.wikipedia.org/wiki/Haversine_formula which takes the curvature of the Earth into account, and also the fact that one degree in longitude is a different distance depending on the latitude.