On Mon, Feb 28, 2011 at 10:45 PM, Jay Pipes <jaypi...@gmail.com> wrote: > for those of a like-minded curiosity about these things. From the > wikipedia article on this same subject: > > "The term Metadata is an ambiguous term which is used for two > fundamentally different concepts (Types). Although a trite expression > "data about data" is often used, it does not apply to both in the same > way. Structural metadata, the design and specification of data > structures, cannot be about data, because at design time the > application contains no data. In this case the correct description > would be "data about the containers of data". Descriptive metadata on > the other hand, is about individual instances of application data, the > data content. In this case, a useful description (resulting in a > disambiguating neologism) would be "data about data contents" or > "content about content" thus Metacontent. Descriptive, Guide and the > NISO concept of Administrative metadata are all subtypes of > metacontent."
And for those wondering why the Glance project uses the term "metadata" to describe data about the image, we, too, have a similar terminology problem: We delineate between the image *data*, which is the raw image file itself, and image *metadata*, which is really data about the image (like disk format, status, etc). To make matters worse, we have the concept of image *properties* which are free-form key/value pairs attached to the image. So, neither Glance nor Nova uses the term *metadata* properly, for what it's worth :) -jay _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
