Eyeball theorem

The Eyeball theorem, often encountered in the context of algebraic geometry, is a humorous and informal way of illustrating certain geometric concepts involving curves and their behavior. However, it's not a standardized theorem with a formal proof in the same way as established mathematical principles. In a more specific mathematical context, the term "eyeball" might refer to visualizing properties of curves or surfaces, particularly in terms of intersections, singular points, or other geometric characteristics.