Social signals are metrics that measure how much people interact with your content on social media. From likes, to shares, to comments; each of these signals contributes to an overall number that tells search engines like Google how much people like your content.
You can easily buy social signals here.
Social Signal Counter. Instantly find your website popularity in social media platforms like Facebook, Twitter, Pinterest, LinkedIn, Stumbleupon and Reddit.
For some reason, the result may sometimes be 0.