Here is a summary of the changes which have been introduced by Joomla 2.5 (some of which were included in the earlier releases 1.6 & 1.7), in the areas of functionality, administrative interface, and templates design compared with Joomla 1.5 the previous long term stable release. Readers who require detailed information about the changes to the underlying programming structure should refer to the Joomla website for more information.
- A new Access Control System (ACL) which enable the site developer to create unlimited groups and combinations of permissions, removing one of the biggest limitations of Joomla 1.5 and 1.0. Control exactly what users can view and can do on your website. This feature will increase the capability of Joomla to tackle a much wider range of online applications.
- Unlimited levels of hierarchy in the category tree used to classify content. Previously only two levels were possible, sections and categories. Now you can define as many sub levels of categories as required. Allows the building of much more complex data structures.
- One-click updating facility - Joomla security updates for the core software and extensions may be applied easily from within Joomla instead of requiring FTP or shell access. The control panel provides an early indication that new updates are available.
- Improved search Engine. A new faster, natural language search engine has been added to the Joomla core with improved features. This provides a more 'Google' experience when searching a large Joomla website with features including auto-completion and stemming, the ability for the search to use the root of the word to locate additional matches.
- Ease of use. Many small but important changes have be made to the user interface to make it easier to use (e.g. Save & New buttons, Save as Copy and tickboxes for Module Menu Assignment), more consistent and less prone to unexpected errors during editing.
Differences between Joomla 1.5 and 2.5
- SEO improvements. Much more control over SEO factors as part of the core code. e.g. Articles can change the page title and page header separately, better multi language support.
- One-click extensions package installer, i.e. components, modules and plugins can all be packaged and installed from a single file.
- Improved multi-language support (e.g. A separate home can be set for different languages, language )
- General Improvements
- Built in Captcha function for user forms
- Enhanced Template Manager including Template Styles, and ability to define multiple layouts.
- Support for Microsoft IIS server and MS SQL
- Simple layouts can be defined for Blog style websites
- Custom text blacklists in articles
- Simple customisation tool for overriding words in screen text, system emails etc
- Customisable offline mode image