Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
GetResponse is an email marketing app that allows you to create a mailing list and capture data onto it.
Google Analytics is a free web analytics service that tracks and reports website traffic.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Varnish is a reverse caching proxy.