Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google Publisher Tag (GPT) is an ad tagging library for Google Ad Manager which is used to dynamically build ad requests.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Open Graph is a protocol that is used to integrate any web page into the social graph.