The Intersection snap
As the Object Snap name Intersection suggests, this Object Snap will let you snap to the intersection point of any two curves. This snap is very useful and it is recommended that you keep this snap active most of the time. To use this snap, select it from the Object Snap menu then select a draw command and move your cursor close to the intersection point of two curves. A green cross indicating the Intersection snap will show up, as shown:
The Intersection snap will show for almost every kind of intersecting drawing. The Intersection snap also shows up for curves that are apparently intersecting on a 2D plane:
In the preceding example, the two lines are not actually intersecting, but when we track a line toward the second one, the point of apparent intersection is highlighted and you can snap to that point.