This script enables a nice, quick search engine that can help your visitors find information that they are interested in more easily. The larger the site, the more important the search engine becomes.
Warning: This search engine searches all of the ASCII (text) files on your site. This includes HTML, PERL, plain text files, etc. Since there is no way to limit the search engine, if any of these files contain sensitive information, either encrypt the files or remove them from your site. This is a smart move anyway - you should not store sensitive information on your web site without encryption.