Tags are an important element of so-called „Web 2.0“. In addition to changing the metadata of the document itself, DC-X allows the user to add tags to the document – a great way of organizing documents for personal or departmental use (and you don’t need „update permissions“ on a document to add tags to it).
Tags belong to either a user or a group of users: When you create a new tag, it’s your choice to create it as a personal (private) tag or to make it owned by one of the groups you belong to (meaning anyone in the group can see, apply, or change the tag).
For more specific permissions, tags can be shared with multiple other users or groups. When setting up sharing for a tag, you specify which of these actions will be allowed: Applying the tag, removing the tag from documents it’s already used for, renaming the tag, deleting the tag.
In DC-X, tags are more than simple strings: Each tag is a combination of a metadata field and a value. By default, your tag is supposed to be a simple keyword, but you can also specify that your tag represents a person, a city, or a geo location.
We’re also planning to let users make use of lists and controlled vocabulary when tagging, so that they can use your carefully-cultivated thesaurus terms or lists of names (with „autocomplete“ while the user is typing for faster input).
While tags are kept in a „flat“ structure and don’t have an inherent hierarchy, the DC-X user interface allows you to „drill down“: You’re starting with one tag, then you’re being offered all the other tags used in conjunction with the first one as a one-click filter. Click on a second tag, and you see the tags used in conjunction with the first two, and so on… This frees you from single-hierarchy structures („have I put this under ToDo/ClientName or under ClientName/ToDo?“), you can start from any tag.
A powerful new feature is tag groups (internally called „combi tags“): You can group tags together, which makes for a great shortcut for applying multiple tags at once. Example: Create a tag group named „Roskilde Festival 2009“, set the sub-tags „Country: Denmark“, „City: Roskilde“, „Event: Roskilde Festival“, „Keywords: Music“, „Keywords: Concert“. Apply this tag group to all your Roskilde articles and photos. Now you don’t just have one-click access to them, but you’ll also be able to find them when clicking on the generic „Concert“ tag.
Differences compared to DC5: Instead of tags, DC5 had collections (hierarchical collections in the Picture Desk client) which had a similar purpose, but didn’t support metadata fields, tag groups or dynamic drill-down. Also, DC5 collections could not be used on a regular search form („limit search results only to documents in collection X“), and when displaying a document you couldn’t see which collections it was in – DC-X tags can do both.