Edit in JSFiddle

$(document).ready(function() {
    $('#btnConvert').click(function(e) {
        var strVal = $('#txtValue').val();
        if (strVal.length == 0) {
            $('#dvValue').html('Please enter something');
        }
        else {
            var strMD5 = $.md5(strVal);
            $('#dvValue').html("MD5 string of <b>" + strVal + "</b> is <b>" + strMD5 + "</b>");
        }
        e.preventDefault();
    });
});

<p><u>Using jQuery MD5 Plugin</u></p><br/>
Enter Value : <input type="text" id="txtValue" />
<br/><br/>
<input type="button" id="btnConvert" value=" Convert to MD5 "/>
<br/><br/>
<div id="dvValue"></div>