Apache is a free and open-source cross-platform web server software.
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.
MailChimp for WordPress is an email marketing plugin that enables you to build subscriber lists.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Pure CSS is a set of small, responsive CSS modules that can be used in web projects.
WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture and a template system.
WP Fastest Cache is one of a number of plugins for WordPress designed to accelerate the performance of your website.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.