Every one working as Drupal Developer must know how to customize the layout of any module output i.e. theming functions and hook_theme...The similar functionality of customizing modules output is also exist in Joomla. i.e. Joomla is similarly powerfull enough to utilise the MVC  architecture to control over layout of modules and components easily.

To Do the customization you only require to add the default.php file ( mostly found under tmpl folder of a module) in your current template i.e. like this

1 Create a folder called html in the current template.

2. Create another folder in above mentioned folder called mod_module_name_to _override.

3. add the default.php file of the module you want to customize in above created folder and then you can change the code of default.php according to your desire.

Hence the path to your new customized file should be similar to this:

templates/your_template_folder/html/mod_module_name_to_override/layout_file_name.php