GeoNames
Encyclopedia
Geographical database
A geographical database is a database of geographic data, such as countries, administrative divisions, cities, and related information. Such databases can be useful for websites that wish to identify the locations of their visitors for custimization purposes....
available and accessible through various Web services, under a Creative Commons
Creative Commons
Creative Commons is a non-profit organization headquartered in Mountain View, California, United States devoted to expanding the range of creative works available for others to build upon legally and to share. The organization has released several copyright-licenses known as Creative Commons...
attribution license.
Database and web services
The GeoNames database contains over 10,000,000 geographical namesToponymy
Toponymy is the scientific study of place names , their origins, meanings, use and typology. The word "toponymy" is derived from the Greek words tópos and ónoma . Toponymy is itself a branch of onomastics, the study of names of all kinds...
corresponding to over 7,500,000 unique features. All features are categorized into one out of nine feature classes and further subcategorized into one out of 645 feature codes. Beyond names of places in various languages, data stored include latitude
Latitude
In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the Equator. The latitude is an angle, and is usually measured in degrees . The equator has a latitude of 0°, the North pole has a latitude of 90° north , and the South pole has a...
, longitude
Longitude
Longitude is a geographic coordinate that specifies the east-west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees, minutes and seconds, and denoted by the Greek letter lambda ....
, elevation, population, administrative subdivision and postal code
Postal code
A postal code is a series of letters and/or digits appended to a postal address for the purpose of sorting mail. Once postal codes were introduced, other applications became possible.In February 2005, 117 of the 190 member countries of the Universal Postal Union had postal code systems...
s. All coordinates
Geographic coordinate system
A geographic coordinate system is a coordinate system that enables every location on the Earth to be specified by a set of numbers. The coordinates are often chosen such that one of the numbers represent vertical position, and two or three of the numbers represent horizontal position...
use the World Geodetic
Geodetic
Geodetic is an adjective meaning pertaining to geodesy, the science of measurement of the earth. See also:* Geodetic system* Geodetic airframe...
System 1984 (WGS84).
Those data are accessible free of charge through a number of Web services and a daily database export. The Web services include direct and reverse geocoding
Geocoding
Geocoding is the process of finding associated geographic coordinates from other geographic data, such as street addresses, or zip codes...
, finding places through postal codes, finding places next to a given place, and finding Wikipedia
Wikipedia
Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Its 20 million articles have been written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone with access to the site,...
articles about neighbouring places.
Wiki interface
The core of GeoNames database is provided by official public sources, of which quality may vary. Through a wikiWiki
A wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...
interface, users are invited to manually edit and improve the database by adding or correcting names, move existing features, add new features, etc.
Semantic Web integration
Each GeoNames feature is represented as a Web resourceResource (Web)
The concept of resource is primitive in the Web architecture, and is used in the definition of its fundamental elements. The term was first introduced to refer to targets of Uniform Resource Locators , but its definition has been further extended to include the referent of any Uniform Resource...
identified by a stable URI
Úri
Úriis a village and commune in the comitatus of Pest in Hungary....
. This URI provides access, through content negotiation
Content negotiation
Content negotiation is a mechanism defined in the HTTP specification that makes it possible to serve different versions of a document at the same URI, so that user agents can specify which version fit their capabilities the best...
, either to the HTML wiki page, or to a RDF
Resource Description Framework
The Resource Description Framework is a family of World Wide Web Consortium specifications originally designed as a metadata data model...
description of the feature, using elements of the GeoNames ontology
Ontology (computer science)
In computer science and information science, an ontology formally represents knowledge as a set of concepts within a domain, and the relationships between those concepts. It can be used to reason about the entities within that domain and may be used to describe the domain.In theory, an ontology is...
. This ontology describes the GeoNames features properties using the Web Ontology Language
Web Ontology Language
The Web Ontology Language is a family of knowledge representation languages for authoring ontologies.The languages are characterised by formal semantics and RDF/XML-based serializations for the Semantic Web...
, the feature classes and codes being described in the SKOS
SKOS
Simple Knowledge Organization System is a family of formal languages designed for representation of thesauri, classification schemes, taxonomies, subject-heading systems, or any other type of structured controlled vocabulary. SKOS is built upon RDF and RDFS, and its main objective is to enable...
language.
Through Wikipedia articles URL linked in the RDF descriptions, GeoNames data are linked to DBpedia
DBpedia
DBpedia is a project aiming to extract structured content from the information created as part of the Wikipedia project. This structured information is then made available on the World Wide Web. DBpedia allows users to query relationships and properties associated with Wikipedia resources,...
data and other RDF Linked Data
Linked Data
In computing, linked data describes a method of publishing structured data so that it can be interlinked and become more useful. It builds upon standard Web technologies such as HTTP and URIs, but rather than using them to serve web pages for human readers, it extends them to share information in a...
.