Simple JS-ToolTip <abbr>

qtip.css

div#qTip {
 padding: 3px;
 border: 1px solid #666;
 border-right-width: 2px;
 border-bottom-width: 2px;
 display: none;
 background: #FFF9DF; /* #999; */
 color: #444; /*#FFF; */
 font: normal 10px Verdana, Arial, sans-serif;
 text-align: left;
 position: absolute;
 z-index: 1000;
}
abbr.glossary, abbr.myClass {
 border-bottom: dotted;
 border-color: #666;
 border-width: thin;
 cursor: help;
}

qtip.js

// qTip - CSS Tool Tips - by Craig Erskine
// http://qrayg.com
//
// Multi-tag support by James Crooke
// http://www.cj-design.com
//
// Inspired by code from Travis Beckham
// http://www.squidfingers.com | http://www.podlob.com
//
// Copyright (c) 2006 Craig Erskine
// Permission is granted to copy, distribute and/or modify this document
// under the terms of the GNU Free Documentation License, Version 1.3
// or any later version published by the Free Software Foundation;
// with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
// A copy of the license is included in the section entitled "GNU
// Free Documentation License".
 
var qTipTag = "a,label,input,abbr"; //Which tag do you want to qTip-ize? Keep it lowercase!//
var qTipX = 0; //This is qTip's X offset//
var qTipY = 25; //This is qTip's Y offset//
 
//There's No need to edit anything below this line//
tooltip = {
  name : "qTip",
  offsetX : qTipX,
  offsetY : qTipY,
  tip : null
}
 
tooltip.init = function () {
    var tipNameSpaceURI = "http://www.w3.org/1999/xhtml";
    if(!tipContainerID){ var tipContainerID = "qTip";}
    var tipContainer = document.getElementById(tipContainerID);
 
    if(!tipContainer) {
      tipContainer = document.createElementNS ? document.createElementNS(tipNameSpaceURI, "div") : document.createElement("div");
        tipContainer.setAttribute("id", tipContainerID);
      document.getElementsByTagName("body").item(0).appendChild(tipContainer);
    }
 
    if (!document.getElementById) return;
    this.tip = document.getElementById (this.name);
    if (this.tip) document.onmousemove = function (evt) {tooltip.move (evt)};
 
    var a, sTitle, elements;
 
    var elementList = qTipTag.split(",");
    for(var j = 0; j < elementList.length; j++)
    {
        elements = document.getElementsByTagName(elementList[j]);
        if(elements)
        {
            for (var i = 0; i < elements.length; i ++)
            {
                a = elements[i];
                sTitle = a.getAttribute("title");
                if(sTitle)
                {
                    a.setAttribute("tiptitle", sTitle);
                    a.removeAttribute("title");
                    a.removeAttribute("alt");
                    a.onmouseover = function() {tooltip.show(this.getAttribute('tiptitle'))};
                    a.onmouseout = function() {tooltip.hide()};
                }
            }
        }
    }
}
 
tooltip.move = function (evt) {
    var x=0, y=0;
    if (document.all) {//IE
        x = (document.documentElement && document.documentElement.scrollLeft) ? document.documentElement.scrollLeft : document.body.scrollLeft;
        y = (document.documentElement && document.documentElement.scrollTop) ? document.documentElement.scrollTop : document.body.scrollTop;
        x += window.event.clientX;
        y += window.event.clientY;
 
    } else {//Good Browsers
        x = evt.pageX;
        y = evt.pageY;
    }
    this.tip.style.left = (x + this.offsetX) + "px";
    this.tip.style.top = (y + this.offsetY) + "px";
}
 
tooltip.show = function (text) {
    if (!this.tip) return;
    this.tip.innerHTML = text;
    this.tip.style.display = "block";
}
 
tooltip.hide = function () {
    if (!this.tip) return;
    this.tip.innerHTML = "";
    this.tip.style.display = "none";
}
 
window.onload = function () {
    tooltip.init ();
}