A container image digest, image digest, or digest, is a unique, immutable identifier for a container image to deploy.

For Docker images, the digest is a SHA256 hash of the docker image. The docker image of a digest is a set of layers instead of a single file. The digest may specifically represent a hash of the image or an image manifest JSON document, which has the information about the image.

Pushing a new image onto an existing tag when the old image still has a digest updates that tag. You can delete digests as needed.