Why using Nofollow tag for search engine optimization

The attribute should be applied to comments pages that usually contain references to untrusted sources and hyperlinks. These links transfer users to shady sites that could cause the trust declining. Such a situation reduces a page's position in search results.

Apply rel-nofollow to place partner links and advertisements on your web site. This is exactly how Google recommends implying paid links. Moreover, the link mass will not be transferred to external sites if you use this tag.

The attribute should be applied to internal links like "Registration" or "Enter" pages that have no priority in indexing. You can find this advice enlisted in Google recommendations.

Never apply Noindex and Nofollow tags to links that serve for website internal interlinking that helps to increase promotion efficiency by distributing link mass among your site pages. Use of Nofollow in HTML code sufficiently reduces the productivity of internal interlinking and complicates the promotion.

Nofollow tag must not be implied in most paid external links to the site used for promotion. These type of links cannot influence the link mass transfer from donor-sites and will not affect promotion effectiveness.

Nevertheless, Nofollow links can be used to make the site link profile common to search engines, thus reducing sanction risk.

In some cases, Nofollow attribute should be applied to external links that are implied in the page.

Building links targeting outside web pages, apply Nofollow to avoid users' trust declining and to preserve link mass.

Most paid links used for site promotion should not contain this attribute as it can influence page position in search results.

Do not use Nofollow for internal interlinking to avoid negative influence on site promotion.