> Markdown version of [Overview](https://vaadin.com/docs/v8/framework/addons/addons-overview). Section index: [llms.txt](https://vaadin.com/docs/v8/framework/llms.txt)

# <a id="addons.overview"></a>Overview

In addition to the components, layouts, themes, and data sources built in into the core Vaadin library, many others are available as add-ons. [Vaadin Directory](https://vaadin.com/directory/) provides a rich collection of add-ons for Vaadin, and you may find others from independent sources. Add-ons are also one way to share your own components between projects.

## <a id="installing"></a>Installing

Installing add-ons from Vaadin Directory is simple, just adding a Maven or an Ivy dependency, or downloading the JAR package and and dropping it in the web library folder of the project.

[Image: addon architecture]

Role of the widget set

Most add-ons include *widgets*, client-side counterparts of the server-side components used in the Vaadin Java API, as illustrated in [Role of the widget set](#figure.addons.maven.widgetset). The *widget set* needs to be compiled into the application widget set.

Adding the dependency in Maven projects and compiling the widget set is described in ["Using Add-ons in a Maven Project"](https://vaadin.com/docs/v8/framework/addons/addons-maven.md#addons.maven). The section also describes how to use the online compilation and CDN services during development.

For Eclipse projects that use Ivy for dependency management, see ["Installing Add-ons in Eclipse with Ivy"](https://vaadin.com/docs/v8/framework/addons/addons-eclipse.md#addons.eclipse). You can also download and install add-ons from a ZIP-package, as described in ["Downloading Add-ons from Vaadin Directory"](https://vaadin.com/docs/v8/framework/addons/addons-downloading.md#addons.downloading).

## <a id="add-on-licenses"></a>Add-on Licenses

Add-ons available from Vaadin Directory are distributed under different licenses, of which some are commercial. While the add-ons can be downloaded directly, you should note their license and other terms and conditions. Many are offered under a dual licensing agreement so that they can be used in open source projects for free, and many have a trial period for closed-source development. Commercial Vaadin add-ons distributed under the CVAL license require installing a license key as instructed in ["Installing Commercial Vaadin Add-on License"](https://vaadin.com/docs/v8/framework/addons/addons-cval.md#addons.cval).

## <a id="feedback-and-support"></a>Feedback and Support

After trying out an add-on, you can give some feedback to the author of the add-on by rating the add-on with one to five stars and optionally leaving a comment. Most add-ons also have a discussion forum thread for user feedback and questions.