Glossary
Domain authority
Domain authority is a third-party score estimating how likely a website is to rank, based mostly on the links pointing at it.
It is worth knowing that Google does not use it. It is invented by SEO tool vendors as a convenient shorthand, and different tools give the same site different numbers.
Why it matters to you
It is useful for comparison and useless as a target. Chasing the score rather than the thing it estimates is how businesses end up buying links that do nothing.
An example
A site scoring 20 with fifteen genuine local links will out-rank a site scoring 40 built from bought directory links, because the score is a guess and the links are the reality.
Where this comes up: search engine optimisation .