var speed =80;   
var demo =document.getElementById("demo");   
var demo1 =document.getElementById("demo1");   
var demo2 =document.getElementById("demo2");   
demo2.innerHTML = demo1.innerHTML;   
function Marquee() {   
    if (demo2.offsetWidth - demo.scrollLeft <= 0)           
        demo.scrollLeft -= demo1.offsetWidth;   
    else {   
        demo.scrollLeft++;   
    }   
}   
var MyMar = setInterval(Marquee, speed);   
demo.onmouseover = function() {   
    clearInterval(MyMar);   
}   
demo.onmouseout = function() {   
    MyMar = setInterval(Marquee, speed);   
}