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4th chunk of `content/guides/rust/build-images.md`
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REPOSITORY                TAG               IMAGE ID       CREATED         SIZE
docker-rust-image         latest            8cae92a8fbd6   3 minutes ago   123MB
```

You should see at least one image listed, including the image you just built `docker-rust-image:latest`.

## Tag images

As mentioned earlier, an image name is made up of slash-separated name components. Name components may contain lowercase letters, digits, and separators. A separator can include a period, one or two underscores, or one or more dashes. A name component may not start or end with a separator.

An image is made up of a manifest and a list of layers. Don't worry too much about manifests and layers at this point other than a "tag" points to a combination of these artifacts. You can have multiple tags for an image. Create a second tag for the image you built and take a look at its layers.

To create a new tag for the image you built, run the following command.

```console
$ docker tag docker-rust-image:latest docker-rust-image:v1.0.0
```

The `docker tag` command creates a new tag for an image. It doesn't create a new image. The tag points to the same image and is just another way to reference the image.

Now, run the `docker images` command to see a list of the local images.

```console
$ docker images
REPOSITORY                TAG               IMAGE ID       CREATED         SIZE
docker-rust-image         latest            8cae92a8fbd6   4 minutes ago   123MB
docker-rust-image         v1.0.0            8cae92a8fbd6   4 minutes ago   123MB
rust                      latest            be5d294735c6   4 minutes ago   113MB
```

You can see that two images start with `docker-rust-image`. You know they're the same image because if you take a look at the `IMAGE ID` column, you can see that the values are the same for the two images.

Remove the tag you just created. To do this, use the `rmi` command. The `rmi` command stands for remove image.

```console
$ docker rmi docker-rust-image:v1.0.0
Untagged: docker-rust-image:v1.0.0
```

Note that the response from Docker tells you that Docker didn't remove the image, but only "untagged" it. You can check this by running the `docker images` command.

```console
$ docker images
REPOSITORY               TAG               IMAGE ID       CREATED         SIZE
docker-rust-image        latest            8cae92a8fbd6   6 minutes ago   123MB
rust                     latest            be5d294735c6   6 minutes ago   113MB
```

Docker removed the image tagged with `:v1.0.0`, but the `docker-rust-image:latest` tag is available on your machine.

## Summary

This section showed how you can use `docker init` to create a Dockerfile and .dockerignore file for a Rust application. It then showed you how to build an image. And finally, it showed you how to tag an image and list all images.

Related information:

- [Dockerfile reference](/reference/dockerfile.md)
- [.dockerignore file](/reference/dockerfile.md#dockerignore-file)
- [docker init CLI reference](/reference/cli/docker/init.md)
- [docker build CLI reference](/reference/cli/docker/buildx/build.md)

## Next steps

In the next section learn how to run your image as a container.
Title: Tagging and Removing Docker Images
Summary
This section elaborates on tagging Docker images, emphasizing that a tag is simply a pointer to an image's manifest and layers, not a copy. It demonstrates how to create a new tag and verify that both tags share the same IMAGE ID. It then explains how to remove a tag using the `docker rmi` command, clarifying that this only untags the image, and the image itself remains until all tags are removed. Finally, it summarizes the steps covered and provides links to related documentation before introducing the next section on running the image as a container.