Black Hat Knight — a simple example of cloaking

Cloaking is a blackhat SEO trick that shows nice and readable pages to human visitors, while showing highly optimised (and often ugly) pages to the search engine spiders. The simplest way to cloak is to detect the user-agent string of the visitor/spider, and to adapt your content based on that. It can be done with a variety of methods, like the .htaccess file or php code...

This particular page is cloaked from Msnbot, a spider that's very quick to index new pages. As a matter of fact, MSN search is one of the fastest indexing search engines about. However, MSN spidered the page a lot but didn't care to index it at first. Luckily, I also cloaked it from Slurp, and Yahoo was very helpful to index the page (at last). And now MSN has it as well.

Most cloakers will be targetting Google(bot) though — it is still the most popular, hence the most abused bot…

To see what the cloaked page looks like, look at the cached snapshot of this page from this Yahoo results page or from MSN's equivalent. Alternatively, use the Firefox browser in combination with the User-Agent Switcher extension, temporarily set your user-agent string to that of the Slurp or MSN bot, then hit the refresh button. You can also use a cloaking detector but since my page doesn't target googlebot, it's no use here.

Please note that it took quite a while for this particular page to be indexed… It may have been held back manually, but I'm not saying that it has. In any case, the subject is rather controversial, and I presume that none of the search engines likes to be a cloaking "victim".