What is Referrer?

Referrer - also known as HTTP referer, is an HTTP header field that identifies the webpage or resource that linked to the current page being requested by a client. This information helps webmasters understand how users arrive at their website and which sources are driving traffic.

The referrer header is automatically sent by a user's browser when they click on a link to navigate from one page to another. It can also be used for tracking purposes in online advertising campaigns, allowing advertisers to see which websites are sending them traffic.

In addition, referrer data can help website owners identify broken links and monitor the effectiveness of marketing strategies. However, it's important to note that some browsers may block or remove this information for privacy reasons.