You can publish a node in a container as a parent anchor or child anchor to designate hierarchical attachment points between a container and nodes external to that container. Furthermore, when a container is locked, Maya only allows parenting relationships to be made or broken on internal nodes that are published as anchors.
For example, a node representing a character’s shoulder could be encapsulated in a container representing a character’s arm. This shoulder node could then be set as the child of the character’s body node, which would be outside the arm container. In this case, the shoulder is published as a child anchor.
While Maya does not require that you publish a node as an anchor in order to parent it to an external node (unless the container is locked), publishing a node as an anchor gives many benefits. Publishing a parent or child anchor tells Maya to use the published name when recording modifications to their parenting during file referencing. This enables you to change the name of the node in a referenced scene without breaking a parent scene. Published anchors also allow you to transfer these parent/child relationships when using the Transfer Attribute Values option. Finally, they allow you to see nodes when a container is in Black Box mode. For more detailed information, see Published nodes.
To publish a parent or child anchor
The group node is set as the container’s parent anchor or child anchor.
You can also auto-publish a node as a parent and child anchor when creating a container.
To auto-publish a parent and child anchor
Maya creates a container with the selected node encapsulated in it. This node is set as the root node, parent anchor, and child anchor.
Similar to the above method, you can set a node as a published parent and published child anchor when you are assigning it as a root node from the Assets > Node Publishing > Publish as Root Node option window.
To unpublish a parent or child anchor