Joomla template is set of files created with purpose to wrap up the content of the CMS into HTML tags with CSS rules and interractive JavaScript. The minimal template contains two files: templateDetails.xml and index.php.

Joomla reads templateDetails.xml to determine features template supports and files it contains. It also may contian definition of block placeholdes in the index.php file, template parameters, and author information.

index.php is the main template file. It contains page layout, may include CSS files, script files, and images.

Theme may be parametrized, in this case templateDetails.xml should contain definition of parameters, which usually dropdown lists and sets of radio buttons. Selected parameter values are saved in params.ini and this file should be writable by Joomla and listed in the templateDetails.xml file.

The index.html file, which you may see in a lot of Joomla themes, are usually blank and used to prevent Web server with directory indexing turned on from displaying theme files. This file, as other theme files, should be listed in templateDetails.xml in the files section.

The template_thumbnail.png file contains small preview of the Joomla CMS with the template applied. This PNG file should have the following dimensions: width 206px and height 150px. This file does not directly impact on how theme works, but it very usefull for users when they selecting the theme for their sites.

Read more:

• Joomla! 1.5 Template Tutorials Project