Speed reading is a technique for increasing reading speed whilst still maintaining conscious awareness of the material being read.
The basic idea behind speed reading is that the reading process is slowed down by sub-vocalisation - reading the words out to ourselves in our head. Changing our reading so that we read visually (i.e. keeping internal silence) means we can go faster and take in material phrase by phrase or line by line, rather than word by word. The usual way of doing this is to silence the internal voice by turning down the volume or similar. Fingers are then used as a guide to speed up the reading process.
Speed reading differs from PhotoReading in that the material is consciously processed and so a conscious understanding is maintained immediately. In photo-reading the material is processed unconsciously and so conscious understanding has to be elicited subsequently. Hence their applications are different.
Dr Ian Gregory, 2004