It all started with a simple post on Twitter by a user who asked an innocent question: do you usually see these lines of light at night? Seeing the hidden lines isn't a superpower. The question is much simpler: you may have astigmatism and you may not know it.In the Twitter post, this user shows us what people who have astigmatism see and what those who don't see. The former should not drive at night without glasses, because as you will see in the video and although they may not know it, their vision is very limited.At this point, and unless you aren't reading this article through lenses for people who have astigmatism, you're probably wondering what that is. Astigmatism occurs when your eye isn't round like a soccer ball, but rather shaped like a rugby ball.When this happens, light isn't reflected directly into the retina but through various points, giving rise to those lines that prevent you from seeing well. It can be corrected with simple glasses or contact lenses, or with surgery.Check out the video above to see if you pass the test!