Eyes don't see in frames per second. The difference between a computer and actual movement is that computers just change the color of pixels, while our eyes get input from light. We stop perceiving movement at what would translate to 60fps, which if why things like car tires or helicopter blades seem like they are stationary wheels or are slowly spinning backwards. if something on a computer screen went 150fps, we would be able to see it just fine. The more FPS we have on a computer, the better we are able to react, meaning we have better accuracy and reaction time in games.