Folks have abused keywords in a misguided effort to manipulate the engines. This involves “stuffing” keywords into text, URLs, meta tags, and links. Unfortunately, this tactic almost always does more harm than good for your site. The best practice is to use your keywords naturally and strategically. If your page targets the keyword phrase “Eiffel Tower” then you might naturally include content about the Eiffel Tower itself, the history of the tower, or even recommended Paris hotels. On the other hand, if you simply sprinkle the words “Eiffel Tower” onto a page with irrelevant content, then your efforts to rank for “Eiffel Tower” will be in vain. The point of using keywords is not to rank highly for all keywords, but to rank highly for the keywords that people are searching for when they want what your site provides.