What is the canonical link in SEO?
A canonical link element is an HTML element that helps webmasters prevent duplicate content issues by specifying the "canonical" or "preferred" version of a web page as part of search engine optimization.
A canonical link component is associate hypertext mark-up language component that helps webmasters stop duplicate content problems by specifying the "canonical" or "preferred" version of an internet page as a part of program improvement.
Canonical is an HTML element that helps webmasters prevent duplicate content issues.
When your website has two URL it means your website has a canonical issue. For example, if you write www.apptunix.com and they have show error or if you write http://www.apptunix.com show you see a page related to mobile application development company. it means Google think its two websites for the different domain. and its negative hit for you.