Advantages of using on-line computers to record eye movement data are discussed. These advantages include computer scoring of eye movement data, greater accuracy in identifying the location of a fixation, greater accuracy in determining timing variables such as saccade duration and fixation duration, and the capability of controlling stimulus presentation as a function of eye location. Emphasis is placed on the latter of these advantages. The characteristics of an on-line eye movement recording system are briefly described, followed by a description of the research using such a system to investigate reading, integration of information across eye movements, eccentric vision, and picture processing and visual search.