Why is the x-axis on a graph usually horizontal and the y-axis is usually vertical?
Actually, it always is that way. ^^ My teachers drilled that into my head. I don’t exactly know how it started—I do have a guess, though. However, I’m pretty sure a lot of people just happened to do it (or one notable person) and then it became the standard, ‘right’ way. If there is any method to this madness, it might be: 1) When naming variables, people commonly start with x or a and then proceed to name the remaining variables letters after x and a. So, x, y, z, and a, b, c. 2) When drawing a graph, perhaps people tended to draw the horizontal axis first and then the vertical one (which I do). 3) People naturally began to gravitate towards naming the horizontal axis x and then the vertical one y. 4) Someone finally decided to standardize it to better teach the young children of the world. ^^ And it’s much more convenient with a label than to call it the ‘horizontal axis’, which is a mouthful if you’re trying to explain a graph.
