Modules are built-in 'extensions' that are used to display your content to the website visitors. Using our example in the last recipe, you saw that you can make your site show a different template, based on the 'section' that is called. A module can be used in a similar fashion, showing components or other modules such as the Login module (also known as mod_login).
The module positions are placeholders, which are used to display content with the associated module.
Here is an example of the Login module being displayed in the left module position on the default Joomla! template rhuk_milkyway:
The designer ...