# Volumes
A volume is a data storage area that can be mounted into a container to provide persistent storage. Unlike bind mounts, volumes are independent of the underlying OS and are fully managed by the Docker Engine.
A volume with the **external** flag was created outside of Portainer, which means Portainer has limited knowledge on it compared to one created within Portainer. A label of **unused** means that Portainer cannot see any applications that are using this volume. This label may also appear on **external** resources because of the limited information available.
In Portainer you can view a list of the volumes on your environment, add new volumes and remove existing volumes.
{% content-ref url="volumes/add" %}
[add](https://docs.portainer.io/user/docker/volumes/add)
{% endcontent-ref %}
{% content-ref url="volumes/remove" %}
[remove](https://docs.portainer.io/user/docker/volumes/remove)
{% endcontent-ref %}
If you're running Docker Swarm or the Portainer Agent on your environment, you can also browse existing volumes on that environment.
{% content-ref url="volumes/browse" %}
[browse](https://docs.portainer.io/user/docker/volumes/browse)
{% endcontent-ref %}
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://docs.portainer.io/user/docker/volumes.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
