# What is a module?

## Frontend Modules (End Users)

Modules extend IDEA experience by adding new functionalities for the end users.

{% hint style="info" %}
All frontend modules are optionals and IDEA administrators can decide whether or not they want to install them individually.
{% endhint %}

* [Virtual Desktop Interface (VDI)](https://app.gitbook.com/o/ewXgnQpSEObr0Vh0WSOj/s/QthiamUzKn8KJLl0hYBf/ "mention")
* [HPC WorkLoads](https://app.gitbook.com/o/ewXgnQpSEObr0Vh0WSOj/s/LGamNPuOYtjAP3GFfRJO/ "mention")

## Backend Modules (Cluster Admins)

Backend modules are mandatory and automatically installed during your initial IDEA deployment. Users do not directly interact with them.

* [Cluster Manager](https://app.gitbook.com/o/ewXgnQpSEObr0Vh0WSOj/s/GtBrWw9T1qCJK2QCOTW2/ "mention")
* Directory Services
* Global Settings
* ...