Apache is a free and open-source cross-platform web server software.
AWeber is an email marketing service.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PayPal is an online payments system that supports online money transfers and serves as an electronic alternative to traditional paper methods like checks and money orders.
Priority Hints exposes a mechanism for developers to signal a relative priority for browsers to consider when fetching resources.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
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.