Dofollow Link - It is a kind of hyperlink which enhances the ranking of your site as it acts as a backlink that is counted by search engines. Very simple dofollow links allow all search engines to follow them and reach our website.
Example of Dofollow Link:
Nofollow Link - An HTML attribute value used to instruct search engine bots that a hyperlink should not influence the ranking of the link target in search engine’s index. Very simple nofollow links attributes do not allow search engine bots to follow link.
Example of Nofollow Link:
<a href=”http://www.google.com/” rel=”nofollow”>Google</a>