CMS
Content management system - information system used for the management and organization of the joint process of creating, editing and managing content.
CMS Joomla!
CMS written in PHP and JavaScript languages and uses a MySQL database, and others. It is free software distributed under the GNU GPL.
Extensions Joomla!
Special web-applications, allowing to expand the functionality of the CMS Joomla! There are five types of extensions for Joomla: components, modules, plugins, templates and languages.
JKassa - Component
The bulk of the online store is responsible for the organization: the categories of products, files, forms, currencies, menus, etc. Also, the component is carried out order management, buyers, reports...
JKassa - Modules
Additional extensions that allow the buyer to receive quick access to some elements of the store, such as a list of categories, shopping cart, product filter, new products...
JKassa - Plugins
Additional extensions to extend the functionality of the main component. They help integrate third-party web systems still as comments, payment system...