Breaking out of the walled garden

Computer mapping (aka "GIS") has traditionally been a separate world within computing, with its own tools, data representations, and data repositories. However, there is much to be gained by bringing geographical information out of its walled garden, and fully integrating it into the normal information flows of the web. Web content often concerns things and events that have locations on the earth, and this location data is relevant to the selection, depiction, and processing of the content by people or computers. In an ideal future, web data will be tagged with geographical information whenever relevant, and mapping tools will be available on demand for visualization and navigation of geotagged content.

Microcontent

Geotagging fits perfectly into a large scale trend in the evolution of the web-- a trend which Nova Spivak has formulated under the slogan "Metaweb":

On the existing Web, information is typically published in large chunks-- "sites" comprised of "pages." In the coming microcontent-driven Metaweb, information will be published in discrete, semantically defined "postings" that can represent an entire site, a page, a part of a page, or an individual idea, picture, file, message, fact, opinion, note, data record, or comment.

(From The Birth of "The Metaweb")

The web is already rapidly progressing in this direction. For example all of the major news sites publish RSS feeds. (RSS is a standard format which structures the content of a news feed or weblog into a series of annotated "posts"). Meanwhile, there is equally rapid evolution of the tools for filtering and aggregating content-- the syndication services and search engines.

RDF

RDF is a web standard for data integration, developed at the W3C. RDF is built from a series of "vocabularies". For example, there are vocabularies for weblog posts (RSS), for personal descriptions (FOAF), for restaurants (ChefMoz), for time and events (RDFCalendar), for geometry (RDFGeom2d), and for geography (RDFIG Geo). These vocabularies can be mixed in individual RDF documents or data stores, allowing aggregation of desriptions from all available terminologies. As a result, RDF provides a technical foundation for integrating microcontent from diverse sources.

Geo-tagging

Geotagging, that is, annotating items of web content with location or other geographical information, fits perfectly into this evolutionary direction, because once content has been disassembled into its elementary units, those units-- whether they be individual stories in an RSS news feed, events in an RDF event calendar, or individual photographs in an EXIF annotated archive-- can be tagged with geographical information using standards that are already in place (See the Geotag Now! page nearby).

Map Bureau Tools

Web information flows have sources (publishers of information), end points (people or software applications) and, in between, engines for routing and transforming the flows (the syndicators, aggregators, and analyzers).

PointMapper is our contribution at the end point. PointMapper supports flexible embedding of map widgets into web pages, in a manner that can be adapted to the needs of varied applications, both in the matter of presentation, and functionality.

RDFMapper is a web service for extracting mappable content from information sources in the RSS or RDF formats, and constructing interactive pointMapper maps presenting the content. RDF is the data representation underlying the semantic web project.

*Mapper is a simple tool to aid creation of geotagged content. It takes the form of a web-based interface that allows users to interactively assign locations to things that interest them - webpages, photographs, notes, weblog entries, etc. *Mapper emits content in RDF that is converted by RDFMapper into interactive pointMapper maps.

RDFMapper and *Mapper are beta-test versions.

Thus our own tools can be plugged together to support a primitive end-to-end information flow of the kind discussed above. But our primary intention is to make tools that connect in standard ways to arbitrary sources, processors, and mappers of geotagged data. As a simple example, RDFMapper is easily configured to map the contents of the GeoURL database of geotagged websites.

Here is a diagram of the primary geotagged web data flows:

The Geo-annotation Community

A few links appear below to web mapping efforts that are driven by geo-annotation of web content, rather than by the specialized data representations of the traditional GIS community.

space.frot.org RDF for geo-annotation

thingster.org An aggresive generalization of weblogging; geo-annotation included,

geourl.org Geo-tagging web pages

GeoInfo Wiki at esw.w3.org

Worldkit Flash maps of locations from RSS feeds