how to create text inside textbox

how to create text inside textbox

for example

http://social.msdn.microsoft.com/en-US/GettingStarted/ the site contains text "Search MSDN with Live search" in a textbox.

I want: 

1.If we click into it the textbox the text(ex:"Be Cool") will disappear.

2.If I click,enter some text ,remove it,and click outside of it,then the text("Be Cool") should get appeared in the text box.

thanks,

bharathi.

 
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