How it works...

An Odoo module is a directory containing code files and other assets. The directory name used is the module's technical name. The name key in the module manifest is its title.

The __manifest__.py file is the module manifest. It contains a Python dictionary with information about the module, the modules it depends on, and the data files that it will load.

In the example, a minimal manifest file was used, but in real modules, we will want to add a few other important keys. These are discussed in the Completing the module manifest recipe, which we will see next.

The module directory must be Python-importable, so it also needs to have an __init__.py file, even if it's empty. To load a module, the Odoo server will import it. This will cause the code in the __init__.py file to be executed, so it works as an entry point to run the module Python code. Due to this, it will usually contain import statements to load the module Python files and submodules.

Known modules can be installed directly from the command line using the --init or
-i option. This list is initially set when you create a new database, from the modules found on the addons path provided at that time. It can be updated in an existing database with the Update Module List menu.