what is this code function ?

Can you tell me ?
i would like to know what is function of this code.

Thanks

Code:

---

<script type="text/javascript">
<!--
/***********************************************
* Show Hint script- ? Dynamic Drive (www.dynamicdrive.com)
* This notice MUST stay intact for legal use
* Visit http://www.dynamicdrive.com/ for this script and 100s more.
***********************************************/
               
var horizontal_offset="10px" //horizontal offset of hint box from anchor link

/////No further editting needed

var vertical_offset="0" //horizontal offset of hint box from anchor link. No need to change.
var ie=document.all
var ns6=document.getElementById&&!document.all

function getposOffset(what, offsettype){
var totaloffset=(offsettype=="left")? what.offsetLeft : what.offsetTop;
var parentEl=what.offsetParent;
while (parentEl!=null){
totaloffset=(offsettype=="left")? totaloffset+parentEl.offsetLeft : totaloffset+parentEl.offsetTop;
parentEl=parentEl.offsetParent;
}
return totaloffset;
}

function iecompattest(){
return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
}

function clearbrowseredge(obj, whichedge){
var edgeoffset=(whichedge=="rightedge")? parseInt(horizontal_offset)*-1 : parseInt(vertical_offset)*-1
if (whichedge=="rightedge"){
var windowedge=ie && !window.opera? iecompattest().scrollLeft+iecompattest().clientWidth-30 : window.pageXOffset+window.innerWidth-40
dropmenuobj.contentmeasure=dropmenuobj.offsetWidth
if (windowedge-dropmenuobj.x < dropmenuobj.contentmeasure)
edgeoffset=dropmenuobj.contentmeasure+obj.offsetWidth+parseInt(horizontal_offset)
}
else{
var windowedge=ie && !window.opera? iecompattest().scrollTop+iecompattest().clientHeight-15 : window.pageYOffset+window.innerHeight-18
dropmenuobj.contentmeasure=dropmenuobj.offsetHeight
if (windowedge-dropmenuobj.y < dropmenuobj.contentmeasure)
edgeoffset=dropmenuobj.contentmeasure-obj.offsetHeight
}
return edgeoffset
}

function showhint(menucontents, obj, e, tipwidth){
if ((ie||ns6) && document.getElementById("hintbox")){
dropmenuobj=document.getElementById("hintbox")
dropmenuobj.innerHTML=menucontents
dropmenuobj.style.left=dropmenuobj.style.top=-500
if (tipwidth!=""){
dropmenuobj.widthobj=dropmenuobj.style
dropmenuobj.widthobj.width=tipwidth
}
dropmenuobj.x=getposOffset(obj, "left")
dropmenuobj.y=getposOffset(obj, "top")
dropmenuobj.style.left=dropmenuobj.x-clearbrowseredge(obj, "rightedge")+obj.offsetWidth+"px"
dropmenuobj.style.top=dropmenuobj.y-clearbrowseredge(obj, "bottomedge")+"px"
dropmenuobj.style.visibility="visible"
obj.onmouseout=hidetip
}
}

function hidetip(e){
dropmenuobj.style.visibility="hidden"
dropmenuobj.style.left="-500px"
}

function createhintbox(){
var divblock=document.createElement("div")
divblock.setAttribute("id", "hintbox")
document.body.appendChild(divblock)
}

if (window.addEventListener)
window.addEventListener("load", createhintbox, false)
else if (window.attachEvent)
window.attachEvent("onload", createhintbox)
else if (document.getElementById)
window.onload=createhintbox

function MM_openBrWindow(theURL,winName,features) { //v2.0
  window.open(theURL,winName,features);
}
//-->

---

Thank you in advance.

Quote:

---

Description: "Show Hint" script displays an attractive hint box containing additional explanation on any item on your page. A hint box pops up next to the item when the mouse moves over it with relevant hints or useful information. A classic use of "Show Hint" is with your form fields, to better explain to the user how to fill them out.

---

see http://www.dynamicdrive.com/dynamicindex16/showhint.htm

Thank you :)