Input for display screen fields can be alphanumerically restricted so that, for
example, users can enter only numbers in a field requesting a Social Security number,
or they can input only letters where a person’s name is required. If numbers
are input where only letters are allowed, the computer may alert the user via audio
output that the field was filled out incorrectly.
The chief advantage of the input/output form interface is that the printed version
of the filled-in form provides excellent documentation. It shows field labels as
well as the context for entries. In addition,Web forms can return incomplete forms
to the user with an explanation of what data must be entered to complete the
transaction. Often, fields with missing data are marked with a red asterisk.Webbased
documents can be sent directly to billing if a transaction is involved, or they
can go directly to a consumer database if a survey is being submitted.Web-based
forms push the responsibility for accuracy to the user and make the form available
for completion and submission on a 24-hour, 7-day-a-week, worldwide basis.