Most people imagine that when they read their eyes move smoothly from one word to the next and that when they reach the end of a line they move smoothly to the beginning of the next line.
But when our eyes move relative to what we are looking at, that object will be out of focus. Try it when you are next in a car. Look out of a side window and keep your eye still. The edge of the road will be out of focus and blurry. The eye operates a little like a camera. It is only able to capture a sharp image when it is still in relation to what it is focused on.
When you read, your eye can only focus on text when it is still. This means that your eye moves in a series of jumps and pauses. It is during the pauses that you take in information. These are called saccadic eye movements. There are usually four or five of these per line of text for a normal book. If you learn to control these movements by using a visual guide, such as a pen or your finger, you will speed up your reading.