Well you need to use JavaScript if you intend to do this client-side.
If the information is of any significant importance I recommend doing server-side validation as well which can be accomplished with PHP, ASP, or a smörgåsbord of other technologies.
Here is one site you can visit to find examples done in JavaScript
:
http://javascript.internet.com
: )
Rich
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Smiling Souls
http://www.smilingsouls.net
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