how to remove text in textbox, when clicked in it, or the reverse?

Hi everybody,
Let's say I have a textbox to enter the the date information. Initially, I want to display valid date format, like MM/DD/YYYY, and when user clicks in the  textbox I want the 'MM/DD/YYYY' to be cleared automatically. And if when user clicks on the outside without entereing data, the MM/DD/YYYY shall be displayed automatically...
 I could not find a related property of asp.net textbox 2.0, could you provide any related link, references?
Thanks for any help..
 
...