ABSTRACT
Language can be conveyed through several input modes. For the majority of people through most of human history, the principal mode was speech, with the deaf and some other little-documented minorities using visible gestures. The chapter focuses on the opportunities offered by the study of braille reading, the most common form of tactile reading. The notion of using the haptic system of blind people for written communication had inspired many attempts through the ages. The critical step that Braille accomplished consisted of rejecting any constraint from existing visual characters. In one-handed reading, the reading finger scans the line from left to right, then returns to the following line. The scanning movements of skilled readers are smooth, with few variations in speed. In optical reading, the reader can adjust his or her ocular exploration to the demands of comprehension to a considerable degree.
