Feed level links are followed by one or more categories:
<category scheme="http://schemas.sage.com/sdata/categories" term="collection" label="Resource Collection"/>
In this example, the feed carries only one category element. This category element classifies the feed as being an SData resource collection - a collection in the SData scheme. See SData Scheme section for details.
Providers can add more categories to the feeds they produce. But they should never have more than one category in the SData scheme, identified by the http://schemas.sage.com/sdata/categories URL.
SData providers SHOULD include this category element in their feeds