As everybody from SEO fraternity understand Google algorithm considers more than 200 signals to determine ranking. Page Rank was an important signal, but recently Google confirmed that PR will not be updated going forward instead will be considering DA & PA (Domain Authority & Page Authority) as major ranking signals. Even Though DA & PA considers multiple factors, relevancy and popularity of incoming link will be one of the major deciding factors. In last couple of years the importance has beenshifted from quantity of backlinks to quality of backlinks. So in short if you have a set of unnatural spammy backlinks pointing to your site, it may hurt your site rather than helping in ranking. We have put down step by step process for how to remove bad backlinks / unnatural backlinks using disavow links tool in Google Webmasters.