# Extensions

Extensions are used to add functionality to your periodic application. Extensions are loaded, initialized, configured and mounted during the periodic initialization process.

Extensions are typically stitched together to build a customized web application or API.

* [ What are Periodic Extensions? ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/02-what-are-periodic-extensions.md)
* [ How do Periodic Extensions work? ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/03-how-are-extensions-loaded.md)
* [ How are Extensions loaded? ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/03-how-are-extensions-loaded.md)
* [ What are some common Extensions? ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/04-what-are-some-common-extensions.md)
* [ Installing and Removing Extensions ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/05-installing-and-removing-extensions.md)
* [ Configuring Extensions ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/06-configuring-extensions.md)
* [ Creating Extensions ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/07-creating-your-own-extensions.md)

NEXT: [ What are Periodic Extensions? ](https://github.com/repetere/periodicjs/blob/master/doc/extensions/02-what-are-periodic-extensions.md)