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.
Jetpack is a popular WordPress plugin created by Automattic, the people behind WordPress.com.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
Typekit is an online service which offers a subscription library of fonts.
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.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.