JavaScript Snow falling Effect for HTML

Snow effect that can be easily added to web pages

1. Copy and paste this script to body section
2. upload bellow png image to the web directory

 <script type="text/javascript">  
  //Configure below to change URL path to the snow image  
  var snowsrc="snow.gif"  
  // Configure below to change number of snow to render  
  var no = 10;  
  // Configure whether snow should disappear after x seconds (0=never):  
  var hidesnowtime = 0;  
  // Configure how much snow should drop down before fading   
 ("windowheight" or "pageheight")  
  var snowdistance = "pageheight";  
 ///////////Stop Config//////////////////////////////////  
  var ie4up = (document.all) ? 1 : 0;  
  var ns6up = (document.getElementById&&!document.all) ? 1 : 0;  
      function iecompattest(){  
      return (document.compatMode && document.compatMode!="BackCompat")?  
  document.documentElement : document.body  
      }  
  var dx, xp, yp;  // coordinate and position variables  
  var am, stx, sty; // amplitude and step variables  
  var i, doc_width = 800, doc_height = 600;   
  if (ns6up) {  
   doc_width = self.innerWidth;  
   doc_height = self.innerHeight;  
  } else if (ie4up) {  
   doc_width = iecompattest().clientWidth;  
   doc_height = iecompattest().clientHeight;  
  }  
  dx = new Array();  
  xp = new Array();  
  yp = new Array();  
  am = new Array();  
  stx = new Array();  
  sty = new Array();  
  snowsrc=(snowsrc.indexOf("dynamicdrive.com")!=-1)? "snow.gif" : snowsrc  
  for (i = 0; i < no; ++ i) {   
   dx[i] = 0;            // set coordinate variables  
   xp[i] = Math.random()*(doc_width-50); // set position variables  
   yp[i] = Math.random()*doc_height;  
   am[i] = Math.random()*20;     // set amplitude variables  
   stx[i] = 0.02 + Math.random()/10; // set step variables  
   sty[i] = 0.7 + Math.random();   // set step variables  
           if (ie4up||ns6up) {  
    if (i == 0) {  
     document.write("<div id=\"dot"+ i +"\" style=\"POSITION: absolute; Z-INDEX: "+ i  
  +"; VISIBILITY: visible; TOP: 15px; LEFT: 15px;\">  
 <a href=\"http://dynamicdrive.com\">  
 <img src='"+snowsrc+"' border=\"0\"><\/a><\/div>");  
    } else {  
    document.write("<div id=\"dot"+ i +"\" style=\"POSITION: absolute; Z-INDEX: "+ i  
  +"; VISIBILITY: visible; TOP: 15px; LEFT: 15px;\">  
 <img src='"+snowsrc+"' border=\"0\"><\/div>");  
    }  
   }  
  }  
  function snowIE_NS6() { // IE and NS6 main animation function  
   doc_width = ns6up?window.innerWidth-10 : iecompattest().clientWidth-10;  
           doc_height=(window.innerHeight && snowdistance=="windowheight")?   
 window.innerHeight : (ie4up && snowdistance=="windowheight")? iecompattest().  
 clientHeight : (ie4up && !window.opera &&   
 snowdistance=="pageheight")? iecompattest().  
 scrollHeight : iecompattest().offsetHeight;  
   for (i = 0; i < no; ++ i) { // iterate for every dot  
    yp[i] += sty[i];  
    if (yp[i] > doc_height-50) {  
     xp[i] = Math.random()*(doc_width-am[i]-30);  
     yp[i] = 0;  
     stx[i] = 0.02 + Math.random()/10;  
     sty[i] = 0.7 + Math.random();  
    }  
    dx[i] += stx[i];  
    document.getElementById("dot"+i).style.top=yp[i]+"px";  
    document.getElementById("dot"+i).style.left=xp[i] + am[i]*Math.sin(dx[i])+"px";   
   }  
   snowtimer=setTimeout("snowIE_NS6()", 10);  
  }  
      function hidesnow(){  
           if (window.snowtimer) clearTimeout(snowtimer)  
           for (i=0; i<no; i++) document.getElementById  
 ("dot"+i).style.visibility="hidden"  
      }  
 if (ie4up||ns6up){  
   snowIE_NS6();  
           if (hidesnowtime>0)  
           setTimeout("hidesnow()", hidesnowtime*1000)  
           }  
 </script>