What is RSS/Atom and what problems does it solve?

Both are data formats in XML to store a list of feed entries, such as text or
media items in a structured manner.

* RSS is an evolving standard (and it is a bit vaguely defined sometimes).
* Atom is a RFC standardized format:
  "RFC4287 - The Atom Syndication Format".

RSS/Atom is commonly used for:
* Keeping track of news from newssites (headlines and content).
* Keeping track of software releases.
* Listings of podcasts with maybe some .mp3 file attachment aka an enclosure.
* Bittorrent listings with a .torrent or magnet link.

In general this makes organizing and keeping track of content more structured
and convenient.  As a user you can more quickly filter interesting news and
don't have to use all the different site navigations.
