Hi,
<style type="text/css"> div { width:40px; height:40px; margin:10px; float:left; border:2px solid blue; } </style> <script type="text/javascript" src="js/jquery-1.3.2.min.js"></script> <script type="text/javascript"> $(function(){ var divs = $('div','body'); var divSize = width(divs); console.log(divSize); }); </script> <body> <div></div> <div></div> <div></div> <div></div> <div></div> <div></div> <div></div> <div></div> <div></div> </body> I want to know the width of div, i do like this, why the console says width(divs) is not defined ? I see in some plugins just doing it this way with no problem at all