Modules are small blocks of content that can be displayed in positions on a web page. The menus on this site are displayed in modules. The core of Joomla! includes 17 separate modules ranging from login to search to random images. Each module has a name that starts mod_ but when it displays it has a title. In the descriptions in this section, the titles are the same as the names.
Navigation modules help your visitors move through your site and find what they need.
Menus provide your site with structure and help your visitors navigate your site. Although they are all based on the same menu module, the variety of ways menus are used in the sample data show how flexible this module is.
A menu can range from extremely simple (for example the top menu or the menu for the Australian Parks sample site) to extremely complex (for example the About Joomla! menu with its many levels). They can also be used for other types of presentation such as the site map linked from the "This Site" menu.
Breadcrumbs provide users with information about where they are in a site.