HTML Attribute for <FORM ...>
onReset ="script command(s)"

onReset runs a script when the user resets the form. If onReset returns false, the reset is cancelled. Often when people hit reset they don't really mean to reset all their typing, they just hit it accidentally. onReset gives them a chance to cancel the action.

This code checks with if the user really wants to reset the form: 

<FORM 
 ACTION="/cgi-bin/mycgi.pl" 
onReset="return confirm('Do you really want to reset the form?')"
 >
<INPUT TYPE=TEXT NAME="query">
<INPUT TYPE=SUBMIT> 
<INPUT TYPE=RESET>
</FORM>

This gives us this form:

(Form is not live)

<INPUT ...> >