AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
LiteSpeed is a high-scalability web server.
MailChimp for WordPress is an email marketing plugin that enables you to build subscriber lists.
PHP is a general-purpose scripting language used for web development.
The Events Calendar is a free event management plugin for WordPress.
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.