Table made with dotted lines [web page special effects]

I don’t know if you have seen it. This special effect is to remove the default alt prompt of the picture in the web page

<img src="/u/info_img/2009-06/18/9597_logo.gif" alt="Website Building Academy No. 1 Station"> <img src="/u/info_img/2009-06/18/9597_logo.gif" alt="Website Building Academy No. 2 Station"> <img src="/u/info_img/2009-06/18/9597_logo.gif" alt="Website Building Academy No. 3 Station"> <div style="visibility:hidden;border:0px solid #000000;background-color:#333333;font-size:12px;color:#6699cc;position:absolute;" id =altlayer></div> <script> document.body.onmousemove=quickalt; function quickalt() { if (event.srcElement.hint)event.srcElement.alt=event.srcElement.hint; if(event.srcElement.alt && event.srcElement.alt!='') { event.srcElement.hint=event.srcElement.alt; altlayer.style.visibility='visible'; altlayer.style.left=event.x-1; altlayer.style. top=event.y+16; altlayer.innerHTML=event.srcElement.hint event.srcElement.alt=""; } else altlayer.style.visibility='hidden';} </script>