The AJAX Feed API can return feeds in two formats: JSON and XML. By default, the API returns the feed in the JSON format.
The AJAX Feed API JSON format is an abbreviated, canonicalized version of the original feed. It maps Atom and RSS attributes like title, description, and summary to a set of common JSON properties so that you can access Atom and RSS feeds uniformly. For example, the JSON result format returns RSS attribute description as the JSON property content, just like Atom. Likewise, the RSS element pubDate is returned as the JSON property publishedDate to make the results uniform with Atom feeds. The JSON result format is useful if you only want to access standard RSS and Atom elements, and you don’t want to worry about the differences between feed formats.
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