We recommend making sure all internal links on a domain are marked as follow links. Search engines interpret internal nofollow links as a signal that content is being hidden or unserious.
Search engines take into account what sort of links lead to a specific website and where those links come from. A link from a reputable and trusted website is worth a lot. The “nofollow“-tag signifies to search engines, that this particular hyperlink should not be regarded when analyzing the target website.
Be careful not to misuse the “nofollow” attribute by indiscriminately adding it to internal links. You usually want internal links to be followed as not to interfere with linkjuice.
Nofollow tags were also used in the past to prevent abuse through link spamming (e.g. when the comments section of a reputable website is spammed with links to smaller websites). Meanwhile, Google has introduced a new tag for this case, which can be implemented with the code rel="ugc". (Google source)
The “nofollow” attribute is used in HTML like this:
<a href=“http://domain.com” rel=“nofollow”>Text</a>
If all links on a particular page should have “nofollow” it may also be added to the header in the source code:
<meta name=“robots” content=“nofollow” />