Apache is a free and open-source cross-platform web server software.
PHP is a general-purpose scripting language used for web development.
Twenty Ten is the default WordPress theme for 2010.
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.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.