Remote javascript works by taking the script away from the html coding of the page and then referencing the script by a file. So instead of having all that unsightly coding within your html documents, you can turn it into one line of code. This line of code usually looks like this:
<script language="javascript" src="remote_javascript_file_here.js"></script>
A typical javascript looks like this:
<!--
function MM_swapImgRestore() { //v3.0
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() { //v3.0
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_findObj(n, d) { //v3.0
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
}
function MM_swapImage() { //v3.0
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];}
}
//-->
As you can see with the above coding it is quite messy and takes up quite a lot of space. By using the remote javascript option you can cut down on this unneccesary waste of space.
Another major downfall to using javascript is that search engine spiders can not understand it. Have a look at the above jumble and see if you can understand what it does. Having trouble? That's ok, only hardcore javascript coders can understand this mess. Search engine spiders have the same troubles trying to understand this technobabble.
Search engine spiders work from top to bottom. Meaning, when you click on "View" and then "source", the spider will work from <html> to </html>.