Keyword stuffing is a black hat SEO tactic that webmasters use to inflate the perceived relevance of the website to a specific keyword phrase. Favorite places to stuff keywords are the meta tags, including the title and description tag. Many search engines completely ignore the “keywords” meta tag but still use the title and description tag so the method can still get results.
The method is old, and not usually employed by professional black hat optimizers. It used to be extremely effective in getting rankings and visibility, but the major search engines have algorithms that detect and penalize this behavior.
Keyword stuffing had been used in the past to obtain maximum search engine ranking and visibility for particular phrases. This method is completely outdated and adds no value to rankings today. In particular, Google no longer gives good rankings to pages employing this technique.
The most basic form of keyword stuffing in the content of the page is to make the text the same color as the background of the page, making it initially invisible to humans. It is easily detected, however, using the mouse cursor to select suspicious regions of webpages, as well as looking in Google’s “cache” version of the page which highlights the keywords in your search.
More advanced keyword stuffing utilizes the power of CSS to “Z” position the text behind an image, making it invisible. There is also the possible “absolute” positioning that moves the text far from the center of the page. For the past few years, these techniques have been unmasked and the search engines don’t reward this type of stuffing.
A method that still works is the use of “Noscript” tags, since they are a valid optimization method for displaying an alternative representation of scripted content. This is a place blackhatters abuse, since search engines may index content that is invisible to most visitors.
Nobody can say that there is a perfect keyword density anymore. I personally aim for about 1% but some sites rank well with higher percentages and others with lower. Keyword stuffing is extremely risky since if detected, you most certainly will be penalized. I tried it on a site and went from #1 to #800. It took a couple of months and some begging to get it back - once the stuffed keywords were removed. This tactic is only recommended on completely disposable sites.
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