Apache is a free and open-source cross-platform web server software.
Campaign Monitor is a global technology company that provides an email marketing platform.
Drupal is a free and open-source web content management framework.
Google Optimize allows you to test variants of web pages and see how they perform.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
Open Graph is a protocol that is used to integrate any web page into the social graph.