Persistence of vision

Imagine you have a flashlight and you turn it on for just a split second. You'll notice that the light doesn't just disappear immediately; it seems to linger for a brief moment before fading away. This is because of something called persistence of vision.

Your eyes and brain work together to create an image in your mind based on the light that enters your eyes. When something moves quickly or changes rapidly, your brain doesn't have time to process every single image before moving on to the next one. Instead, it sort of blends them all together into one continuous image.

This means that if you see something that lights up and then disappears quickly, your brain might still "see" it for a little while, even after it's gone. This is the persistence of vision in action.

It's this phenomenon that allows us to see movement in movies and animations, for instance. Even though you're really just looking at a bunch of still images in rapid succession, your brain blends them all together to make it look like things are moving smoothly.

So, to sum it up: Persistence of vision is why things that move quickly seem to blur or linger in your vision for a moment, and it's what allows us to perceive motion in movies and animations. Cool, right?