diff --git a/docs/glossary.md b/docs/glossary.md index 95c8ec9e..6f07a190 100644 --- a/docs/glossary.md +++ b/docs/glossary.md @@ -1,43 +1,70 @@ + + # Glossary -This page contains distribution related terms. For a complete Docker glossary, -see the [glossary in the full documentation set](http://docs.docker.com/reference/glossary/). +This page contains definitions for distribution related terms.
A blob is any kind of content that is stored by a Registry under a content-addressable identifier (a "digest").+
+ Layers are a good example of "blobs". +
An image is a named set of immutable data from which a Docker container can be created.+
+ An image is represented by a json file called a manifest, and is conceptually a set of layers. + + Image names indicate the location where they can be pulled from and pushed to, as they usually start with a registry domain name and port. + +
+A layer is a tar archive bundling partial content from a filesystem.+
+ Layers from an image are usually extracted in order on top of each other to make up a root filesystem from which containers run out. +
A manifest is the JSON representation of an image.
A namespace is a collection of repositories with a common name prefix.+
+ The namespace with an empty prefix is considered the Global Namespace. +
A registry is a service that let you store and deliver images.+
A repository is a set of data containing all versions of a given image.+
A scope is the portion of a namespace onto which a given authorization token is granted.
A tag is conceptually a "version" of a named image.+
+ Example: `docker pull myimage:latest` instructs docker to pull the image "myimage" in version "latest". +
+ +