Joomla templates use module's model of conception of variables, it means that content is splited to separated modules by its type. Structure of data in joomla templates depends on concrete module and all working with content takes place inside of it. Each of modules is independet and completely answer for working with documents of certain type. Documents in joomla templates are described using fixed set of properties, types of documents are definitely fixed. You can extend opportunities of Joomla templates adding new modules, change or editing of existing script. Usualy there is no any system of connectioms between different modules and between different documents of same module. Standard set of content types (modules) is: articles, files, sections, links, news, forum. In spite of evident limitation of data model this system is easy to use. For wideningof functionality you can use three kinds of elements: components, modules and mambots.
Component is a basic tool for widening of functional opportunities of Joomla templates which representsset of scripts for providing certain functionality and has interactive user's interface. There are such components in Joomla templates as forums, file's archives, galleries, systems of gathering statistics and reserve copies and so on. Managment of users, creating of sections, adding and displatying materials - all this implements by components.
Module is one more source for widening of functional opportunities of joomla templates . In most of cases module works for displaying information and serve as addition to seted components. Module can appear on any page in contrast to component which create its own page. Examples of modules are: navigation menus, calendar, list of most popular articles, etc.
Mambot is a function which carry out some manipulations with data before displaying them for visitors of website.at present time there are such groups of mambots: content, editors, serach.
Mambots of content group let realize different manipulations with text of articles: mark out words, add images, remove unnecessary spaces, etc.
Group of mambots "editors" contains visual editors of Joomla templates. Visual editors make adding materials to website more easy.
Main aim of search mambots is a serch of data by different keywords.Distributive of Joomla templates already contains search mambots which lets accomplish search in standard components.
Today there is more then 800 modules and components which satisfy requests of any webmaster. This system suits as for not big website so for big corporate website or huge project.