What is a "no-follow" tag
"No-follow" provides a way for webmasters to tell search engines "Don't follow links on this page" or "Don't follow this specific link." Originally, the nofollow attribute appeared in the page-level meta tag, and instructed search engines not to follow (i.e., crawl) any outgoing links on the page.
<meta name="robots" content="nofollow" />
The reason is social media sites like Facebook and YouTube put a small piece of code called "the no follow" tag into most areas of their site. As the name implies, the "no follow" tells search engines: if someone tries to build backlinks to their site from here, donít follow it. Instead, ignore it.
This was and is done to prevent spammers. If you didnít have the "no-follow" tag, spammers would create thousands of Facebook profiles, LinkedIn profiles, and YouTube accounts just to link those sites back to their website. The "no-follow" breaks the connection you are trying to make between one website and the next, defeating the purpose of a link from the perspective of Google optimization (people can of course still click the link and visit your site directly).
But it' s a fallacy that all social media sites have no-follows. In fact, many sites provide juicy link opportunities. You just need to find them. And we did.
These are all real links, and are entirely legitimate and approved for optimization by Google.