Add the first bit of documentation on how the functionalities system …

…works

docs/docs/developers/features/index.md

@@ -1,3 +1,58 @@
 # Functionalities
 
-_This space is intentionally left blank._
+At the core of Netherlands3D, various functionalities serve as building blocks. Each functionality represents a distinct
+element or feature of the platform, designed to perform specific tasks.
+These functionalities are modular, meaning they can be enabled or disabled individually based on user requirements or
+the needs of a particular project.
+
+This ability to toggle functionalities on and off ensures that you have control over the features you want to deploy in
+your project.
+
+## Configuring Functionalities
+
+Furthermore, each functionality can be individually configured according to specific project requirements. Read more
+about this in detail in the chapter about [configuration](../configuration.md).
+
+Through additional configuration settings, you have the flexibility to adjust the functionality's behavior and
+characteristics to match your project's needs. You'll have access to a broad range of settings allowing you to refine
+each element of your project in detail.
+
+To give some context to the above: examples of additional configuration options are API keys, URLs of services,
+default values for new projects and more.
+
+## How does it work
+
+In Unity's context for the Netherlands3D platform, each functionality is encapsulated in a ScriptableObject. Exploring
+further, you'll discover that each ScriptableObject is highly configurable, granting you the ability to tailor it to
+satisfy specific demands.
+
+### Key Components
+
+#### ScriptableObjects
+The ScriptableObjects for the functionalities can be located in the `Scriptables/Functionalities` folder. Each
+ScriptableObject represents a distinct functionality in the application, and can be configured to define its behavior
+and properties within the application.
+
+#### Functionality System
+
+The code powering the functionality system is hosted within the embedded package named
+`eu.netherlands3d.eu.twin-functionalities`. Digging into this package reveals the design and implementation of
+the system that manages and orchestrates the functionalities.
+
+#### The Functionality Script
+
+At the core, the Functionality script exists as a foundational unit for the ScriptableObject. Here is where you define
+key attributes such as its title, description, ID, and any additional configuration. This script performs the following
+roles:
+
+1. **Title and Description**: The title and description fields of the ScriptableObject are primarily designed for your
+reference in the settings screen of the application.
+
+2. **Functionality ID**: The ID (or code) is used to refer to the functionality from the configuration file. This ID attribute
+is instrumental in organizing and managing configurations of functionalities within the system robustly.
+
+3. **Enabled State**: The enabled state of the functionality indicates whether it's active or inactive. The system can query
+this status to determine the functionality's availability and act accordingly in any part of the application.
+
+4. **Additional Configuration**: The ScriptableObject also includes an additional configuration section where you can define
+supplementary settings and properties that control its behavior within your application.

mkdocs.yml

@@ -75,7 +75,7 @@ nav:
         - 'docs/developers/features/layers.md'
         - 'docs/developers/features/geojson.md'
     - 'Packages':
-        - 'docs/developers/packages/creating-and-managing-packages.md'
+        - 'docs/developers/packages/index.md'
     - 'User interface':
       - 'docs/developers/ui/introduction.md'
       - 'docs/developers/ui/keeping-our-documentation-current.md'