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+# Docker Image Specification v1.

+

+This directory contains documents about Docker Image Specification v1.X.

+

+The v1 file layout and manifests are no longer used in Moby and Docker, except in `docker save` and `docker load`.

+

+However, v1 Image JSON (`application/vnd.docker.container.image.v1+json`) has been still widely

+used and officially adopted in [V2 manifest](https://github.com/docker/distribution/blob/master/docs/spec/manifest-v2-2.md)

+and in [OCI Image Format Specification](https://github.com/opencontainers/image-spec).

+

+## v1.X rough Changelog

+

+All 1.X versions are compatible with older ones.

+

+### [v1.2](v1.2.md)

+

+* Implemented in Docker v1.12 (July, 2016)

+* The official spec document was written in August 2016 ([#25750](https://github.com/moby/moby/pull/25750))

+

+Changes:

+

+* `Healthcheck` struct was added to Image JSON

+

+### [v1.1](v1.1.md)

+

+* Implemented in Docker v1.10 (February, 2016)

+* The official spec document was written in April 2016 ([#22264](https://github.com/moby/moby/pull/22264))

+

+Changes:

+

+* IDs were made into SHA256 digest values rather than random values

+* Layer directory names were made into deterministic values rather than random ID values

+* `manifest.json` was added 

+

+### [v1](v1.md)

+

+* The initial revision

+* The official spec document was written in late 2014 ([#9560](https://github.com/moby/moby/pull/9560)), but actual implementations had existed even earlier

+

+

+## Related specifications

+

+* [Open Containers Initiative (OCI) Image Format Specification v1.0.0](https://github.com/opencontainers/image-spec/tree/v1.0.0)

+* [Docker Image Manifest Version 2, Schema 2](https://github.com/docker/distribution/blob/master/docs/spec/manifest-v2-2.md)

+* [Docker Image Manifest Version 2, Schema 1](https://github.com/docker/distribution/blob/master/docs/spec/manifest-v2-1.md) (*DEPRECATED*)

+* [Docker Registry HTTP API V2](https://docs.docker.com/registry/spec/api/)