How keywords impact search engine rankings

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How keywords impact search engine rankings
Michael Meadhra| February 4, 2004

Keywords are the key to better search engine rankings.That statement, or something like it, has long been a mantra for Web builders. The statement is still true, but dramatic changes in how the leading search engines rank Web pages has forced a significant change in how the statement is interpreted and applied to optimizing Web pages for search engines.

 

Understanding keywords
Keywords are the word or words that a Web visitor types into the input box of a search engine to begin a quest for Web pages on a particular topic. Advanced users can build sophisticated search criteria with multiple keywords joined by Boolean operators, but most users just enter a single word or, perhaps, a two- to three-word phrase.

The search engine then scans its index looking for Web pages that match the visitor's search criteria and returns a list of matching pages, usually ordered by relevance.

The challenge for a Web builder seeking to drive traffic to a site is to anticipate what keywords potential visitors will use to search for sites on a given topic and then engineer the Web pages to get the highest possible relevance ranking in the search engine for those keywords. Divining the appropriate keywords for a given Web site requires an elusive combination of subject knowledge, marketing savvy, luck, and a well-polished crystal ball. After the keywords are identified, weaving them into the fabric of your Web page successfully is often more art than science, but it helps to start with some knowledge of where to put those keywords to achieve the best effect.

Keywords that don't count
In years past, Web builders came up with a list of keywords for a Web page and placed that list in the keyword meta tag. The keyword meta tag was designed to be a reference for indexing page content, and the early search engines relied on it heavily.

However, some Web builders began to abuse the system by stuffing the keyword meta tag with terms that had little or no relevance to the page content. The result was Web pages that got traffic by virtue of high rankings for common search terms, but those pages often had little or no content related to the keyword the visitor was searching for.

This pollution of the keyword meta tags eventually rendered them unreliable tools for indexing Web pages or ranking their relevance. As a result, all the major search engines now ignore the keyword meta tag completely or give its contents very low priority in their page-ranking algorithms.

Keywords that do count
So where on your Web page do the search engines look for matches to the visitor's search criteria? The answer is: throughout the rest of the head and body of the Web page. But that doesn't mean that the location of the keyword on the Web page doesn't make any difference. In fact, the keyword location matters a lot.

Most search engines give a keyword more or less weight based on its location. The weighting algorithms vary at different search engines, and the details of those algorithms are closely guarded secrets. The following list puts the possible keyword locations in approximate order from highest to lowest priority.

• Domain name
• Page title
• Headings (enclosed within h1, h2, h3 tags)
• Body text—The first 2 to 3 KB usually counts more than the rest of the text (if the search engine scans more than that).
• Meta tags—Keywords appearing in the description meta tag still seem to count, as do keywords in some of the Dublin Core meta tags. Some search engines don't ignore the keyword meta tag completely but, rather, discount it heavily—especially if the keyword doesn't appear elsewhere on the page.
• Links—Even keywords buried in the URL, name, or id attributes of a link count in page ranking
• Alt text—Keywords in alt text attributes count toward page ranking. This is yet another reason to take the time to create meaningful alt text for all images.

Keyword repletion is another important factor in page ranking. A page that contains multiple instances of the keyword will generally rank higher than a page on which the keyword appears only once. However, the interaction of keyword placement and repetition is one of the areas where it's almost impossible to second-guess the ranking algorithms.

 

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