How to disappear default text from textbox with javascript

<form action="http://www.domain.com" method="post">
<input type="text" size="25" value="Enter Your Default Text Here" onFocus="
if(this.value == 'Enter Your Default Text Here') 
{
  this.value = '';
}" 
onBlur="if 
(
 this.value == ''
) 
{
 this.value = 'Enter Your Default Text Here';
}" 
/>
<input type=submit value=Submit>
</form>