RSS is a family of XML formats for exchanging news, especially news about Web pages or other Web content. Many dynamic web sites, especially Weblogs or "Blogs" now provide RSS "feeds" of their new or changed content. Another common term for a source of news in RSS format is"Web feed". The basic idea is a simple, brief, and structured XML format which includes only key descriptive elements like author, date, title, narrative description, and hypertext link, elements which help a reader (or an RSS "aggregator" service) decide what source materials are worth examining in more detail. This concise, structured format has also proven useful for publishing all kinds of small, time-sensitive nuggets of information, including Flickr's photo journals, Craigslist classifieds, and local events.
GeoRSS is simple proposal for RSS feeds to also be described by location or Geotagged. We standardize the way in which "where" is encoded with enough simplicity and descriptive power to satisfy most needs to describe the location of Web content. GeoRSS may not work for every use (for example, we provide for only one location per RSS entry), but it should serve as an easy-to-use geotagging language that is brief and simple with useful defaults but extensible and upwardly-compatible with more sophisticated formats like the OGC (Open Geospatial Consortium) GML (Geography Markup Language).
GeoRSS also serves informally as an extension to the W3C geo (point) vocabulary (sometimes also referred to as "GeoRSS"), adding important additional kinds of location (points, lines, and boundaries) as well as other extensibility.
As an example of the need for more than just a point, consider a blog about a kayaking trip. Each RSS entry from such a blog could perhaps be described by a point location, but the entire voyage is clearly a linear path. The line description is especially important for making maps of trips with trip lengths, intersections, and so on. Boundaries are important when you need to specify the edges of an area, which is very useful in talking about things within a certain state, town, or neighborhood for example.
Perhaps the most powerful advantages of GeoRSS feeds will be seen in the possibilities for geographic search and aggregation. More than just getting feeds for a particular city or zip code, using GeoRSS it will be posssible to search with all sorts of geographic criteria. Perhaps all earthquake-related items within 20 miles of your home--delivered to your phone, or a feed of traffic accident items along your daily commute? Once RSS feeds contain geographic location, applications like these and more will be possible.