This element informs the viewer that the document is an
index document. This means that, in addition to being
viewed and read the document can be examined using
a keyword search. Keywords for searching can be passed
from the browser to the server by suffixing, to the URL,
a question mark followed by a list of keywords, separated
by plus signs. Thus if a URL for a searching script were
'http://www.here.ca/cgi-bin/srch'
, you can
send information specifing a search for the string
'instructional' by referencing the URL
'http://www.here.ca/cgi-bin/srch?instructional'
.
The ISINDEX element is usually generated automatically by a server-side script. Recall that it is the server that does the searching, so it is sensible that the server includes this element for situations asking for search information, and omits if when such information is not required. You should not add this element by hand.
To some degree the use of ISINDEX has been supplanted by the more sophisticated FORMS interface. However, not all browsers support FORMS, and the ISINDEX method can be simpler to implement for simple situations.
<HEAD> <ISINDEX> . . </HEAD> <BODY> . body of document (text to be presented) . . </BODY>