Paganduthority
It’s a search ranking from 1 to 100, created by Moz, used to measure the SEO weight that a specific web page carries in the eyes of a search engine.
Domain Authority
It measures how much search engines value a website domain and its pages in order to position them in search results.
B2B (Business to Business)
A business is B2B when it sells to other companies. Google is an example of a company that sells to another company.