# Volumes

A volume is a durable block disk for your instances. Learn the key concepts and find the tasks for creating, resizing, and deleting volumes.

A volume is a durable block disk. Its data lives in durable storage, not on the machine that runs your instance, so it survives instance stops and host failures. You can create a volume on its own, attach it to an instance, grow it, snapshot it, and delete it when you no longer need it. Every volume you create yourself is a durable volume of this kind.

A volume in context, where its content comes from and what it connects to:

- Its content comes from one of three sources: you create it as an empty disk, create it from a protected snapshot, or import a disk image at a URL.
- Its storage class sets its performance tier.
- You attach it to an instance, and you create snapshots from it.

## Key concepts [#key-concepts]

| Concept | Description |
| --- | --- |
| Storage class | The performance tier of a volume. `gp1` is the default and the tier you can select. See [Storage classes](/docs/storage/volumes/storage-classes). |
| Volume states | A volume reports a `status` (such as `AVAILABLE` or `INUSE`) and a separate `modificationStatus` for resizes. Volume operations are asynchronous, and failures show up in these fields. See [Volume states](/docs/storage/volumes/volume-states). |
| Attachment | While a volume is attached to an instance, it reports `INUSE` and names the attachment in `claimRef`. See [Find the instance a volume is attached to](/docs/storage/volumes/find-instance). |

## What you can do [#what-you-can-do]

- [Create a volume](/docs/storage/volumes/create)
- [Import a disk image as a volume](/docs/storage/volumes/import)
- [Resize a volume](/docs/storage/volumes/resize)
- [Find the instance a volume is attached to](/docs/storage/volumes/find-instance)
- [Delete a volume](/docs/storage/volumes/delete)
- [Attach and detach volumes](/docs/compute/instance-storage/attach-detach) (a compute operation)

## Limits and quotas [#limits-and-quotas]

Provisioned volume storage is capped per organization and per project. Creating, importing, and growing a volume all count against the same cap. See [Limits](/docs/platform/reference/limits).

## Related [#related]

- [Snapshots](/docs/storage/snapshots) – point-in-time copies of a volume.
- [`origin storage` commands](/docs/storage/reference/cli)
- [Troubleshoot storage](/docs/storage/troubleshooting)