Nofollow is just one method of 'hiding' links...

There are a lot of threads about "dofollow" blogs, and ways to spot nofollow links. SeoQuake and any number of browser plugins will make them look really obvious. You really shouldn't comment on a blog only because it has "friendly" links, but we all know that. But I get the sense people are only looking for nofollow and then making decisions based on that. This post is something of a warning based on things I've seen.

Here's some basic client script that only works on the 96 % of browsers with javascript enabled:

<span id="comment-938">
<a href="http://www.Home-Page-of-Own-Site.com">Blah blah blah</a>
</span>
[B]...[/B]
<script type="text/javascript">
   document.getElementById('comment-938').innerHTML = '<a href="http://www.example.com">Blah blah blah</a>
</span>';
</script>

HTML:

If the jscript is in an external file, that's going to be a bit harder to spot. InnerHTML is officially an IE only property, but I use the same property on my blog to make the category tree collapsible, and it works in IE, FireFox, Opera, and even Safari ... at least modern versions of each of them.

Even with a nofollow browser plugin, you would have to check the code see that you're not getting credit. FireBug's DOM tree shows the document as it currently exists, so that would show the result of the script. If you're really paranoid, look for mouseover code and anything that runs when the page loads.

There's cloaking; a person can send what looks like a real link to browsers and a nofollow or jscript link to search engines. There's also a plugin that lets you change the user agent FireFox announces itself as.

Last one that comes to mind is really old ( or supplemental ) pages that won't be crawled again. This might be a three year old page or blog post or forum thread that's buried under newer pages. A lot of people make free wordpress themes with sitewide footer links; a blog that adopts one might have 500 indexed pages, but Google will only know about the ones on pages it comes back and crawls. You can make one of them come up by sprinkling a few links to it, but that leaves a lot more to figure out what to do with.

I wrote an article as a guest blogger about all the different ways I've seen fake links, that goes into more detail ... I don't want to write a huge message in here and put everyone to sleep, but I did want to give an overview. I know people make a lot of decisions based on whether or not a forum/blog/directory/whatever uses nofollow or not; whether that's a good idea or not, if you're going to do it, you should check for more than just nofollow.

 

Thanks. but what does this mean in layman's. I cant get to understand other stuff

 

Basically ... this is only for laymen who are making decisions ( pay somebody, comment on a blog, write an article, whatever ) based on the seo value of this links. As opposed to traffic.

For those people, nofollow is one way to make a link not count in Google and Yahoo. Javascript is another, actually it offers severally different ways. Cloaking is normally a way people trick search engines, but it can also be used to trick people who think they're buying a high PR link. In layman's terms, if SE friendliness of a link is important to you, you should look beyond nofollow.

 

I means, be careful. Not all links are created equal!