When considering where to rank your website in search results, search engines consider how many and the quality of links pointed to your domain as part of their algorithm. When developing an SEO (search engine optimization) strategy it is important to compare how many links you have related to your competition. Not your traditional competition, but the competition that ranks better then you for the keywords you are targeting.
Here is a good tool to help you see how many links you have pointed toward website. Ahrefs Site Explorer