Mouseover Tooltips

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<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="author" content="Roderick Divilbiss">
<meta name="copyright" content="© 2005-2010 Roderick Divilbiss">
<title>Mouse Over Tooltip Definitions</title>
<script type="text/javascript">
function showDef(pTerm,e) {
    // to hold the mouse position
    var tempX;
    var tempY;

    // get the mouse position (add a little to Y to be below the term
    if (window.event) {
        tempX = event.clientX + document.body.scrollLeft + 10;
        tempY = event.clientY + document.body.scrollTop;
    } else {
        tempX = e.pageX;
        tempY = e.pageY + 10;
    }

    // based on the term, put the correct definition in the division
    switch (pTerm) {
      case'arbitrage':
          document.getElementById('innerDiv').innerHTML = '<emphasize>arbitrage</emphasize>: The practice of taking advantage of a price differential between two or more markets: striking a combination of matching deals that capitalize upon the imbalance, the profit being the difference between the market prices.'; 
          break;
      case'Brooklyn':
          document.getElementById('innerDiv').innerHTML = '<emphasize>Brooklyn</emphasize>: New York City\'s most populous borough, with 2.5 million residents, and second largest in area.';
          break;
      case'investments':
          document.getElementById('innerDiv').innerHTML = '<emphasize>investments</emphasize>: The active redirection of resources/assets to creating benefits in the future; the use of resources/assets to earn income or profit in the future.';
          break;
      case'Ponzi scheme':
          document.getElementById('innerDiv').innerHTML = '<emphasize>Ponzi scheme</emphasize>: A fraudulent investment operation that pays returns to separate investors from their own money or money paid by subsequent investors, rather than from any actual profit earned.';
          break;
      case'profit':
          document.getElementById('innerDiv').innerHTML = '<emphasize>profit</emphasize>: The making of gain in business activity for the benefit of the owners of the business.';
          break;
      case'redeeming':
          document.getElementById('innerDiv').innerHTML = '<emphasize>redeeming</emphasize>: To recover ownership of by paying a specified sum; for example: to pay off a promissory note.';
          break;
      case'swindlers':
          document.getElementById('innerDiv').innerHTML = '<emphasize>swindlers</emphasize>: Persons practicing quackery or some similar confidence trick in order to obtain money, fame or other advantages via some form of pretence or deception.';
          break;
    }
    // show the division at the mouse position
    document.getElementById('defDiv').style.display='block';
    document.getElementById('defDiv').style.top=tempY+'px';
    document.getElementById('defDiv').style.left=tempX+'px';
}

function closeDef() {
    // if the division is clicked, hide it.
    document.getElementById('defDiv').style.display='none';
}
</script>
<style type="text/css"> 
.definition {
    border-bottom: 3px double #0000FF;
}

#defDiv {
    background-image: url('images/defdivbg.gif');
    background-repeat: no-repeat;
    background-position: left top;
    position:absolute;
    width:257px;
    height:156px;
    display:none;
    padding-top:35px;
    padding-right:45px;
    padding-bottom:10px;
    padding-left:5px;
    font-size:9pt; 
}

#innerDiv {
	margin:0px 20px 10px 10px;
}
</style>
</head>

<body>
<div id="theExample">
Charles Ponzi (March 3, 1882 – January 18, 1949) was one of the greatest <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">swindlers</dfn> in American history. His aliases include Charles Ponei, Charles P. Bianchi, Carl and Carlo. The term &quot;<dfn class="definition" onmouseover="showDef(this.innerHTML,event)">Ponzi scheme</dfn>&quot; is a widely known description of any scam that pays early investors returns from the <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">investments</dfn> of later investors. He promised clients a 50% <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">profit</dfn> within 45 days, or 100% profit within 90 days, by buying discounted postal reply coupons in other countries and <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">redeeming</dfn> them at face value in the United States as a form of <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">arbitrage</dfn>. Ponzi was probably inspired by the scheme of William F. Miller, a <dfn class="definition" onmouseover="showDef(this.innerHTML,event)">Brooklyn</dfn> bookkeeper who in 1899 used the same scheme to take in $1 million.
</div>
<div id="defDiv" onclick="closeDef();"><div id="innerDiv">&nbsp;</div></div>
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</html>
How can you have mouse over tool tip definitions in a styled division?
