Tom Schmitz // Jun 1 2010
When it comes to SEO, placing links on a web page is not simple. There are competing guidelines to consider.
The best links are keyword rich text links. Google uses the link text or anchor text as a signal of relevance. For example, if 100 pages link to http://examplesite.com/baseball with the anchor text baseball, then Google will expect that the target page is relevant for the word baseball.
Sometimes we cannot use a text link. As an example of this, often the first link to a site’s homepage is an image at the top of the page, in the header section. In this case we will place the keywords in the image alt attribute. It’s a fine substitute, but not as strong a signal as a plain text link. This is why SEO consultants usually want clients to change those beautiful image-based navigation bars into text links.
Location matters. Links in the header and content areas are more important than links in the sidebars. Links in the footer offer the least value for SEO.
Link order in HTML markup matters too. The first link on a page is more influential than the second link, the second link is more influential than the third link, and so on.
Already you can see that we have some conflict. If the 10th link on the page is in the main content is it more valuable than the 5th link located in the sidebar? It becomes even more complicated when you consider the rule of first links.
Google only counts each link once no matter how many times it appears on the page. And, Google only counts the first link in the HTML code. This means that you cannot bolster an image link in the header by placing a keyword rich text link to the same URL in the main content area.
In the above example you see several links to the website’s home page.
What would I do in this case? I might suggest a keyword text link to the home page at the very top of the page, above the logo. It may not be the perfect design aesthetic but it will provide maximum SEO value.