Nofollow is a type of links that tells search robots not to consider a link from this site when ranking.
There is a lot of controversy about the usefulness or uselessness of these links. Nofollow links are important to search.
1. Nofollow links help show search engines that your link profile is built naturally mixed with doof.
2. Many experts say that nofollow backlinks are useless, but the nofollow tag is just a mark for crawlers to ignore, but no one knows whether nofollow links are taken into account when ranking or not.