First, there are many pages on the website that do not participate in the ranking. For example, the links to contact us, about us, privacy protection, company profile, website background, etc. can be nofollowed out. Transmitted to them. In addition, some ads on the website, because these ads only allow it to bring IP and traffic, rather than let it weight the search engine, so you can also add this nofollow tag to prevent weight loss.
Second, control the weight distribution and guide the spiders to crawl important content. By using nofollow to intentionally link the link weight to the key section pages or columns that are not sufficiently deep, guide the weight to the pages that need to be ranked. In a limited time, more effective pages are crawled, which increases the number of entries and keyword rankings. It should be noted that for Baidu, even if nofollow is used for the link, the spider will crawl and include it. This tag is only a suggestion that the current page of the search engine does not give weight to this linked page. Included.
At the same time, nofollow is only "suggestion" in terms of weights. Search engines may not fully abide by the webmaster's settings, but have a relatively complete algorithm to determine whether various links are meaningful. Whether this link is recommended or not. The search engine will refer to whether the link has nofollow, but will not just refer to whether the link has the nofollow tag to determine whether the link will export weights.
After all, nofollow just plays a role in assisting website optimization. Seoer does not need to focus too much on it. It may be more meaningful to consider more fundamental issues such as how to optimize the website architecture.