About
A backlink is a link that points to a page.
Technically, it means that the href attribute of the link has the same value than the url of the page.
SEO
backlinks are important for search engine optimization because it's a big component of the reputation of a site web on the web.
- The more external backlinks you have, the more chance you have to be on the search engine result page
- The more internal backlinks you have, the more change you have to get a good score on the page content.
Type
Internal
An internal backlink is a backlink that points to a page of the same origin (same domain).
Example:
- the link https://example.com/myarticle
- on the page https://example.com/homepage
- is an internal backlink
- because they have the same origin https://example.com
External
An external backlink is a backlink that points to a page of another origin (another domain).
Example:
- the link https://example.com/myarticle
- on the page https://news.com/anotherarticle
- is an external backlink
- because the origin differs:
- https://example.com is not equal to https://news.com
It's the basic construct that helps to calculate the domain authority (How popular is a domain).
All backlinks have not the same weight as they can have a rel attribute that design the type of backlink (such as ad, content generated and so on). See the rel attribute
See
- The google search console of google gives you this information at links
