Hello friends,
What is a referral traffic source?
Referral traffic is Google's method of reporting visits that came to your site from sources outside of its search engine. When someone clicks on a hyperlink to go to a new page on a different website, Analytics tracks the click as a referral visit to the second site.
The Google Analytics Traffic Sources section monitors which sources are sending traffic to a site and — with a bit of interpretation — this data can be used to measure the quality of traffic being sent.
Google Analytics recognizes referral traffic as visitors that land on your webpage after clicking on a link from another source (other than search engines).