// form input prefill clear on focus, and reset on blur (if empty)
function prefillClear(field) {
if (field.defaultValue==field.value) {field.value = '';}
else if (field.value == '') {field.value = field.defaultValue;}
}
// usage
<input type="text" name="input1" value="Enter your data" onfocus="prefillClear(this);" onblur="prefillClear(this);" />
// suggest using some further javascript to parse all input fields and apply these functions on domReady. This would save having to put the function calls inline.