How to parse or escape html in javascript??/

Sometimes we want to create html using JavaScript.
like on this page

<div > this is </div>
or may be
<b> hello </b>

for this use

var tagsToReplace = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;'
};

function replaceTag(tag) {
    return tagsToReplace[tag] || tag;
}

function safe_tags_replace(str) {
    return str.replace(/[&<>]/g, replaceTag);
}

link for fiddle is
http://jsperf.com/encode-html-entities

and resource is
http://stackoverflow.com/questions/5499078/fastest-method-to-escape-html-tags-as-html-entities

There are more solutions for this

and finally my favourite one is.

function escapeHTML( string )
{
    var pre = document.createElement('pre');
    var text = document.createTextNode( string );
    pre.appendChild(text);
    return pre.innerHTML;
}