It's not a VHS vs. Beta argument but much like a DVD+RW vs. DVD-RW argument. RSS or atom feed? People who generate syndication feeds have a choice of feed formats.

Have doubts what to use for your site? RSS or atom feed? The various possible ways Atom 1.0 differs from RSS 2.0 can be jotted down as:-

• Required content: RSS 2.0 requires feed-level title, link, and description. It does not require that any of the fields of individual items in a feed be present. Atom 1.0 requires that both feeds and entries include a title (which may be empty), a unique identifier, and a last-updated timestamp.


• Date formats


• Modularity: The elements of the RSS vocabulary are not generally reusable in other XML vocabularies. The Atom syntax was specifically designed to allow elements to be reused outside the context of an Atom feed document. For instance, it is not uncommon to find atom:link elements being used within RSS 2.0 feeds.


• Full or partial content

• Extraction and aggregation: The only recognized form of RSS 2.0 is an document.


• Internationalization: Atom also differs from RSS in that it supports the use of Internationalized Resource Identifiers, which allow links to resources and unique identifiers to contain characters outside the US ASCII character set.


• Categories: RSS 2.0 categories have two parts: label and domain. Atom 1.0 categories have three, with the addition of optional human-readable title.

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(... To read more about it, check here:- RSS or atom feed?).