Domain AuthorityDomain Authority is like MozRank but with more algorithmic factors. It gives you the best indication on how well your domain will perform in search engine rankings and is a score from 0 to 100. Domain authority, or domain trust is important because it will help new pages for your domain to have a better chance of ranking prominently in search results and getting indexed more quickly.
Page AuthorityThe Page Authority is a score for a single web page of a website. This means if you have a webpage from a high ranking website for example a tumblr page, then your page will need to get direct inbound links to rank well. Once your page gains backlinks from other websites, your page authority will increase. Like Domain Authority, the score is from 0 to 100.