Javascript Help

what does this do?

[tonymontana]

Can someone please identify what this scripts does?

Thanks in advance,

<script language="JavaScript">
<!--

function MM_swapImgRestore()
{
var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_preloadImages()
{
var d=document;
if(d.images)
{
if(!d.MM_p) d.MM_p=new Array();
var i,j=d.MM_p.length,a=MM_preloadImages.arguments;
for(i=0; i<a.length; i++)
if (a[i].indexOf("#")!=0)
{
d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];
}
}
}

function MM_swapImage()
{
var i,j=0,x,a=MM_swapImage.arguments;
document.MM_sr=new Array;
for(i=0;i<(a.length-2);i+=3)
if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}

function MM_openBrWindow(theURL,winName,features)
{
window.open(theURL,winName,features);
}

function MM_findObj(n, d)
{
var p,i,x;
if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length)
{
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);
}
if(!(x=d[n])&&d.all)
x=d.all[n];
for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++)
x=MM_findObj(n,d.layers[i].document);
if(!x && d.getElementById)
x=d.getElementById(n);
return x;

}
//-->
</script>

[DrDoc]

Welcome to Webmaster World!

That script is generated by Macromedia DreamWeaver, and it preloads images for use in mouseover effects.