A backlink: -
Backlinks are also called incoming links that help users to shift from one web page to the other web pages. These links play an important part in SEO. When Google search engine views multiple quality backlinks to a page, it considers the page to be more relevant to the search query, which helps in its indexing process and improves its organic ranking on SERPs. This is the example of a backlink leading to another page.
A do follow link: -
A Do-Follow Link, as the name suggests, allows Google link calculator called PageRank to count all the inbound links from other web pages and websites as link points.The higher the link juice or link points are, the greater would be the search ranking of that web page, as these links make the web page appear very relevant and popular to the Google search engines.
A no follow link: -
A No-Follow link is exactly the opposite of a Do-Follow link as such the link attributes do not allow the Google bots to follow them. These links cannot be followed by robots; only humans can do it. No-follow link attributes are structured in the following manner: <a href=”http://www.example.com/” rel=”nofollow”>Link text</a>