Tracking skills are a key part of the reading process. Tracking is the ability to control fine eye movements in order to follow a line of print smoothly. Inability to do so results in the child losing his or her place, skipping or transposing words and may result in struggling with reading comprehension. The reading process involves the eyes making small jumps between words or groups of words. These jumps are called saccades. The brief pause a child makes while looking at the words is call a fixation. After a fixation, a child will move his or her eyes to the next word or group of words, performing another saccade. This precise coordination of jumps and pauses is controlled by one's central and peripheral visual systems. Central vision processes what a child sees in clear detail. Peripheral or side vision, simultaneously locates surrounding objects and lets a child know where to look. In reading, central vision processes the word, while peripheral vision locates the following word and tells a child were to aim his or her eyes next. The integration of these two systems is what allows a child to efficiently move his or her eyes along a line of print without overshooting or undershooting or mistakenly aiming their eyes at lines above or below. A lack of continuous, fluid, simultaneous integration between these two systems results in difficulty with reading smoothly, keeping track of one's place and reading comprehension.