First, the medium of display is not fixed. Viewed as a document, the form may be displayed, printed, typeset, even spoken over the telephone. Different text templates can be used to present different views of the same information. Only the necessary portions of the form need be disclosed to the viewer. Finally, the act of entering values may cause side effects-filling in a patient record may trigger the automatic mailing of a bill.
Natural language seems an attractive proposition for user interfaces.
However, despite the existence of some sophisticated example systems, it has not achieved the maturity of the other techniques discussed here, and its future is still uncertain. It offers the potential of very high expressiveness, combined with ease of use and familiarity for all. Users feel comfortable and are practiced in its use, and need no special training. Set against this is verbosity and the difficulty for many people of typing. Although speaking natural language seems attractive, existing speech recognition systems are highly limited research projects.