<html>
<body>
<isindex action="cgi-bin/search" prompt="Search for:">
<!-- This is equivalent to -->
<form action="cgi-bin/search" method="get">
<span>Search for:</span>
<input type="text"/>
</form>
</body>
</html>
The isindex element creates a simple search text box.
Deprecated
After you press enter, the search terms are sent to the server in the URL query string.
E.g.
http://zuga.net/articles/html-tags/cgi-bin/search?one+two+three
A live example:
N of