Facets are markers on document types that instruct Nuxeo (and any part of the system that cares about them) to behave differently, or that are automatically set on some document instances. The following facets are currently in use by Nuxeo, but others could be defined by code using Nuxeo.
Asset
Marker facet to be set on types which you want to see in the DAM compat view.
Audio
This facet should be set on any type which you want to store a audio. It comes with the file, and audio schemas.
BrowseViaSearch
DamSearch
Marker facet to be set on types used as search document types for DAM compat search content views. Documents with this facet will be listed as DAM saved searches.
Downloadable
FacetedSearch
Marker facet to be set on types used as search document types for content views used in the Faceted search. Documents with this facet will be listed as faceted saved searches.
Folderish
This should be set on types that are to be considered as "folders", and therefore for which a list of children may be displayed in the navigation tree and other user interface areas.
HasRelatedText
This facet can be added dynamically to a document to store arbitrary related text that will be used in the fulltext index for the document. In this way, you can find the document with a fulltext search on more that just what's stored in the document.
This is used for instance to add the Annotations fulltext to the document, or in the Semantic Entities plugin. We'd like to do it for comments as well but it's not done yet.
It can be used by third-parties to add further text.
Of course this requires that the fulltext index includes the relatedtext schema. This is the default, but if you redefine the default index it's important to know.
HasStoryboard
Marker facet to be set on types which you want to generate Storyboard, types on which you already added the Video facet.
HasVideoPreview
Marker facet to be set on types which you want to generate a video preview (screenshot), and on which you already added the Video facet.
HiddenInNavigation
This should be set on types which you don't want to see in regular listings of documents and folders.
Immutable
This is automatically set by the system on document instances which correspond to immutable objects (archived versions and proxies).
MultiViewPicture
Marker facet to be set on types which handle a list of picture views.
NotFulltextIndexable
The document won't be full-text indexed.
Orderable
This should be set on folderish types for which maintaining the order of children is important. (CoreSession.orderBefore can be used only on documents contained in orderable folders.)
Picture
This facet should be set on any type which you want to store a picture. It comes with the file and picture schemas.
Publishable
This should be set on document types for which you want to have publishing.
SystemDocument
The document type corresponds to a system document, not a user-visible document. It is often hidden in navigation as well, but not always, as some system documents (like workflow route models) may need to be visible to administrators or selected users.
Versionable
This should be set on document types for which you want to have versioning.
Video
This facet should be set on any type which you want to store a video. It comes with the file, video and picture schemas.
Task
This facet should be set on any type if you want to use it as the task document created by a workflow. Note that along with the facet, the document type must also have the life cycle "task".