# Create a snapshot
**What are snapshots?**
Snapshots are *images that refer to an original image using Redirect-on-Write to avoid changing the original image.*
**How do you create a snapshot?**
To create a snapshot, *run:*
```bash
$ qemu-img create -f qcow2 -b <base image> -F qcow2 <snapshot image>
```
**What happens if any changes are made to the backing image of a snapshot image?**
If any changes are made to the backing image of a snapshot image, *the snapshot image will be corrupted.*
# Returning to a previous version
**Can a snapshot image be returned to its original state once modified?**
*No*, a snapshot image can't be returned to its original state once modified.
# Modifying the backing file
**How do you find what the backing image is of a snapshot image?**
To find the backing image of a snapshot image, *run:*
```bash
$ qemu-img info <snapshot image>
```
# Temporary snapshots
**What flag can you add when running a QEMU virtual machine to stop changes from being made to the disk image?**
To stop changes from being made to a disk image when running a QEMU virtual machine, you can add *the `-snapshot` flag.*
> [!example] Example of running a QEMU virtual machine as a temporary snapshot
> ```bash
> $ qemu -hda centos-cleaninstall.img -snapshot
> ```