TYPO3 is a modular constructed Content Management System. This means that it consists, on the one hand, of a Core Program (T3 Core), in which the most important functions are integrated, and, on the other, of so-called "extensions", with which the existing performance range of the basic TYPO3 configuration can be extended as desired. The great advantage of extensions: they enable T3 to be connected to any other kind of system, without undergoing any core modifications.
An extension can combine or consolidate several different functions.
We differentiate fundamentally between two types of extension:
- Plug-ins are those extensions which call up functions in the TYPO3 Frontend
- Modules are extensions which deploy additional TYPO3 Backend functions
In addition, extensions are sub-divided into the following groups:
- Backend: Functions that are integrated into the Backend and are available to the Content Manager (e.g.: Rich Text Editor);
- Backend Modules: additional modules in the Backend, which can be separately activated (e.g.: Full Backup);
- Frontend: Functions that are used at the Frontend, but which do not generate their own message window (e.g.: Google Analytics Integration);
- Frontend Plug-in: Extensions, that are shown in the Frontend (e.g.: News system);
- Misc: Other extensions, which cannot be fitted into the above categories (such as libraries, which keep functions available for other extensions);
- Services: Such as an authentication service, used by System Global;
- Examples: Example extensions to clarify something;
- Templates: Basic patterns, such as for showing content;
- Documentation: User or administrator handbooks.
An extension can also contain several plug-ins or modules in order to reach the required performance range. Here is an...
Example for constructing an extension:
- The "Forum" extension
The extension for integrating a forum into TYPO3 consists of four different plug-ins and modules which, when tuned to one another, make available all the required functions:
- Plugin 1: Shows the forum
- Plugin 2: Lists the last 10 forum entries submitted
- Plugin 3: Sends news bulletins to other forum participants
- Modules: Administers the forum in the backend via the Content Manager
- Language localization for extensions
A further advantage of the modular construction of TYPO3 and its extensions lies in the very straightforward way in which different language versions of an extension can be created.
- Every plug-in and module possesses its own locallang.xml file, in which the language used is memory stored. If a new language needs to be added, the locallang.xml only needs to be extended by the appropriate translation. This is a flexible enough task to be carried out by a site editor.
- The language setting can then be changed at a given moment in time.
- Language localization for extensions for the Frontend version:
As a general rule, extensions are stored in the TYPO3 Extension Repository (TER) with a basic localization. For example, in its basic version, the "tt_news" (one of the most used TYPO3 extensions) already exists in 16 different languages.
Additional languages, insofar as they are available, can be quickly and simply downloaded from the TER and installed. The language content of the labels is then simply added to the locallang.xml of the appropriate TYPO3 extension.
The administrator can decide in which languages the Frontend extension should appear. The appropriate language files are then loaded, as soon as the new language has been configured into the the TYPO3 Core-System.
In principle, localizations can be carried out by those other than the original extension developers. More information on how to install new language versions can be found at: http://typo3.org/extensions/translators/