As a newbie blogger, you might come across situations wherein you might be commenting on many distinct blogs leaving a link and you might be getting traffic that has references from that link but still Google does not list them. You might wonder as to why has this situation arisen. The answer is pretty simple to comprehend. These links are nofollow links. In other words, nofollow links are the ones that have rel attribute nofollow. Similarly, dofollow links do not follow the nofollow attribute.