HTTP referrer is a piece of information that is sent by a user's web browser to a website indicating the URL of the webpage that the user came from. In Google Tag Manager, the HTTP referrer can be captured using a user-defined variable.
For example, let's say a user visits a website and clicks on a link that takes them to a new webpage. The new webpage can capture the HTTP referrer information from the user's browser and use it to track where the user came from. This can be helpful in analyzing user behavior on the website and understanding how users navigate through the site.
One real-time example of using HTTP referrer information is in e-commerce websites. When a user clicks on an advertisement on a third-party website and lands on an e-commerce site, the HTTP referrer information can be used to track which advertisement the user clicked on and how effective it was in driving traffic to the site. This can help the e-commerce site optimize their advertising strategy and allocate resources to the most effective channels.
