Yes, you know doing all the work to achieve a decent search engine position is not a joke, Google, Yahoo and the rest of the gang have been investing millions in an effor to try and make search engines display the most relevant content first.
This concept is the trigger of the online battle we face day by day in trying to be a noticeable business on the internet.

Working your site links is a very important part of this effort, it is well knows that although reciprocal linking, or link exchange doesnt have the power one way links impose on search engines, they are also a vital part of your business nowadays.

But ... have you heard of people using cloaking techniques to deceive you ?

A cloaking site basically will try to make a link exchange with your site, wether you use an automatic link checker or you do it manually, the other website will show your link back to you when you go and check it. But ... what happens when Google or Yahoo visits the other website?

The cloakers website will recognize that Googlebot or the Yahoo slurp are visiting , this basically because every visitor to a website announces itself with something called an user agent. In the case of Google, its user agent its usually "GoogleBot" , or in Yahoo "Yahoo slurp". These cloakers will show a different version of the links page to the search engines, one that will not show a link back to your site.

Result ?

They achieve a one way link from your site FREE !
And you ? you get nothing !

These techiques are really unfair but sadly enough are used widely by black hat affiliates and webmasters.

How to find out if they are tricking you ?

The only real way to find this out is to change your user agent to something like 'googlebot' and visit your suspect site, if you get a different page when you visit the site and your link is not there, voila ... youve been cloaked!!!

If you use a browser like Firefox, there is a very nice add on to change your user agent quick, I recommend you to download it.

Click here to download a firefox user agent switcher

I do hope this article gives you a little more background to research on these cloaking techniques NOT TO USE THEM, but to catch those deceivers on the internet. Be fair.

Regards
Felipe