Jay Wessman said in his tutorials that Facebook shares, Twitter retweets and Pinterest repins are backlinks. Others said that links on social networks are all nofollow, and it won't help website ranking. Also, I heard many people saying that nofollow links from websites with high domain autority are a good sign for Google. Who is right? And I had another question: is commenting on blogs with no follow comments helping? What should I write in the "name" field, a common name or a partial match keyword related to my link?