what is parallax method? with example

Parallax is the displacement or the change in the apparent position of the object when viewed from two different points of view. The two points of view have their own line of sights and parallax is measured as half of the angle between the two lines of sights.

When you are traveling in a vehicle and you look around as you are moving, you will see that objects in the distances appear to move more slowly than the objects closer to you. This is the effect of parallax. Nearby objects have a larger parallax than the distant objects, so the parallax can be used to determine distances.

The phenomenon of parallax, when combined with triangulation, will yield the location of the object with considerable accuracy. Astronomers regularly use the parallax method to measure the distances of the closer stars.