Backlinks are links from a page on one website to another. If someone links to your site, then you have a backlink from them. If you link to another website, then they have a backlink from you.
you will get high quality backlinks on high authority sites.
SEO is an acronym that stands for search engine optimization, which is the process of optimizing your website to get organic, or un-paid, traffic from the search engine results page.
When a webpage links to any other page, it's called a backlink. In the past, backlinks were the major metric for the ranking of a webpage. A page with a lot of backlinks tended to rank higher on all major search engines, including Google. This is still true to a large extent.
