It’s a well known fact that linking to other sites or pages dilutes the site’s or page’s rank. Furthermore, if you are a site and link to spammy sites that can impact your site’s overall search engine rankings. This can, therefore, become an issue on blogs where if people comment on your blog and link to their sites. Too many links pointing out of your blog can dilute the overall rank of your own site. In those cases, you can include the ‘nofollow’ tag. This not only makes Google ignore any links going out of your site but also allows your commenters to include links that may be beneficial to your blog readers.
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