👉 In mathematics, a crossing or junction is an intersection of two or more objects. It can be defined as an intersection between two lines, curves, surfaces, or other geometric shapes. For example, consider a rectangle with a square on its bottom side and a circle at the top side. The rectangle has one crossing, which is the intersection between the square and the circle. Similarly, the square has another crossing, which is the intersection between the rectangle and the circle. Crossovers are important in