This technology is quite advanced and devices are now available for routine scanning and storage of printed pages, graphics, etc., which can then be retrieved and displayed when required. In the foregoing paragraphs of this section attempt has been made to explain to you some of the developments taking place as far as input devices are concerned. These developments are to be studied along with other input devices such as card reader, terminal, magnetic tape drive and magnetic disk drive., etc. which existed since long time. Future developments in this direction might include more alternatives to the key board, particularly voice input for commands which is presently available, and wide use of OCR and image 'processing for handling large volumes of information.