From the post:
To accomplish DPLA’s initial goal of creating an aggregation of metadata for cultural heritage materials, the technological infrastructure developed centered on the item-centric library model for description: one descriptive metadata record for each individual digital “object.” While this method works very well for items catalogued singly, like books, it doesn’t reflect the diversity of descriptive practice. Archives and special collections have increasingly focused on aggregate-level description in digital objects, which more closely mirrors their traditional descriptive practices. This kind of description typically creates a single descriptive record for a grouping of related or similar objects.
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