Core The word "core" in Joomla! pertains to the distributed files which are needed to create and administrate a Joomla CMS powered web site. These files can be downloaded from the Joomla website at http://www.joomla.org/download.html. The Joomla "core" also contains some basic functionality to get new Joomla installations working quickly and easily. Included are the user manager, article manager, weblink manager, category manager, contact manager, and menu manager. There is also a template manager with a few basic templates to power the front-end (website/user) view, a module manager with basic modules, plugin manager with basic plugins, and a few other "out of the box" extensions to extend the functionality of a basic Joomla installation. These core's extensions should not be confused with extensions which are available for downloading from the JED (Joomla! Extension Directory). Reference: http://docs.joomla.org/Glossary
Web server The program that uses client/server models. It provides the communication between the browser on the client device and the server where the website files and database are stored. Joomla works with two leading web servers: Apache and Microsoft IIS (Microsoft's Internet Information Server).
JoomlaDay Annually events for Joomla community organized around the world. Joomla.org has a brief list of major Joomla Day since its early days at http://docs.joomla.org/Joomla!_Days/History
