Backlinks are links that are directed towards your website.
Search engine algorithms use backlinks as a measure of the authority of the site (i.e. how may external sites are referring to the content on the site).
These are very important for internet marketing / search engine optimization (SEO). Also known as a back link, backward link, or inbound link. Backlinks are all of the links from other sites that direct users to your site. Backlinks can significantly improve your site’s search rankings, particularly when they contain anchor text keywords relevant to your site. However, a weak backlink or a backlink from a spam site can harm your sites search ranking.
There is no quick and easy means of improving your site ranking on major search engines like Google. It still comes down to good web page content (content is king) and backlinks from relevant (authorative) sites. Be cautious of sites offering to build backlinks. While there are legitimate companies offering these services, there are at least as many of these sites that are scams that could actually harm your site ranking.