a search engine ranking factor used to measure the power of a domain name based on Age, Popularity, Size and other Search Engine Optimisation (SEO) factors. This measurement (scored between 1 – 100) represents how much authority a domain has, to help decide where it should appear in search results and indicating how good your entire domain is. It is calculated by the quantity of links to your site, the quality of those links, and the quantity and quality of those links.