The rel=nofollow attribute in links is a signal to search engine crawlers that this link should not be clicked, as well as passing the weight of the current page.
Example:
<a target="_blank" href="http://www.example.com" rel="nofollow">Link to someone else's site</a>
In addition, there is a meta tag nofollow for the entire page. It
does not prevent from indexing its content, but robots will not follow links on it.
This is what the nofollow meta tag looks like:
<meta name="robots" content="nofollow" />
The original idea was to use nofollow only as a global meta tag. But eventually, it turned out that using the attribute for certain links is more practical and allows you to conveniently adjust the behavior of search engine robots.
Different ways to add the nofollow attribute
If you want to limit navigation to all links on the edited page at once, you need to add a line to the tag, which we have already mentioned above:
The second method differs in that, in addition to blocking robots from following links, it also prohibits indexing the current page. Therefore, it will be irrelevant in situations where the content contained on the page is used for
SEO promotion of the site. If indexing is needed, only the first option is suitable for use.
Why use the nofollow attribute
At first glance, it is not obvious why such tricks are needed. Nevertheless, prohibiting robots from clicking on links performs a number of important functions that effect internal page linking
Links to other people's sites
Many web resources allow users to comment on the content posted, including sharing links in the comments. And in order that the resource does not inadvertently fall under the filter of a search engine because of the presence of unreliable links, it is worth to deal with their moderation. A nofollow attribute or meta-tag, in turn, can close all unnecessary links.
In a different situation, there is no need to use nofollow when citing large trusted resources. Open links to
the quality sites will not decrease your ranking and visibility in search engines, but on the contrary will accelerate
SEO promotion in Google.
Not all sections of the site are equally useful to both the user and the search robots. That means you should not give them weight
sales pages, reducing the chances of the latter to rank high.
Therefore, it makes some sense to use Nofollow in the internal links to the so-called "technical" pages, in the promotion of which you are not interested. These include registration, privacy policy, service data, etc.
Priority page indexing
To begin with, every online resource has its own search engine crawling budget. This is a limit on the crawling of pages by robots for a certain period of time. It is calculated based on rating and popularity of the resource.
It is especially important to monitor your crawling budget if you have a large site that regularly has new content.
So indexing technical and non-sales pages won't do any good or good positions. But it will take away the crawling budget, which just might not be enough to bypass the updated quality content. Especially for such situations, the presence or, on the contrary, absence of the Nofollow attribute will help to direct the robots properly and get rid of problems.
Conclusion
So, let's list when you should leave links open for indexing, in other words, Dofollow (without specifying any attributes):
You're citing or linking to a trusted site.
Internal links to sales pages.
Citing a primary source, such as if you are translating a foreign article.
In what cases is better to lock links with the Nofollow attribute:
In the case of mentioning resources whose reliability is doubtful.
If commenters may share links, which means there is a chance of spam.
Pages of a technical nature whose indexing is unnecessary (registration, profile login, user data, etc.).
You can check the outbound links on the page with our service
site analysis.
And you have a separate list of internal addresses with closed indexing and external addresses with open indexing.
