Tag basics
A tag is a label that you assign to an Amazon resource. Each tag consists of a key and an optional value, both of which you define.
Tags enable you to categorize your Amazon resources by, for example, purpose, owner, or environment. When you have many resources of the same type, you can quickly identify a specific resource based on the tags you've assigned to it. For example, you can define a set of tags for your Amazon Batch services to help you track each service's owner and stack level. We recommend that you devise a consistent set of tag keys for each resource type.
Tags are not automatically assigned to your resources. After you add a tag, you can edit tag keys and values or remove tags from a resource at any time. If you delete a resource, any tags for the resource are also deleted.
Tags don't have any semantic meaning to Amazon Batch and are interpreted strictly as a string of characters. You can set the value of a tag to an empty string, but you can't set the value of a tag to null. If you add a tag that has the same key as an existing tag on that resource, the new value overwrites the old value.
You can work with tags using the Amazon Web Services Management Console, the Amazon CLI, and the Amazon Batch API.
If you're using Amazon Identity and Access Management (IAM), you can control which users in your Amazon account have permission to create, edit, or delete tags.