A 'geo' URI is a URI scheme defined by the Internet Engineering Task Force's RFC 5870 (published 8 June 2010) as:

a Uniform Resource Identifier (URI) for geographic locations using the 'geo' scheme name. A 'geo' URI identifies a physical location in a two- or three-dimensional coordinate reference system in a compact, simple, human-readable, and protocol-independent way.

The current revision of the vCard specification supports 'geo' URIs in a vCard's "GEO" property, and the GeoSMS standard uses 'geo' URIs for geotagging SMS messages.

A 'geo' URI is not to be confused with the site GeoUrl (which implements ICBM address).

A simple 'geo' URI might look like:

where the two numerical values represent latitude and longitude respectively, and are separated by a comma. If a third comma-separated value is present, it represents altitude. The 'geo' URI also allows for an optional "uncertainty" value, separated by a semicolon, representing the uncertainty of the location in meters, and is described using the "u" URI parameter. A 'geo' URI with an uncertainty parameter looks as follows:

GEO or Geo may refer to any of the following:

In computational & scientific use:

In commercial use:

People:

As a group:

As a place:

As a prefix: geo- is taken from the Greek word γη or γαια meaning "earth", usually in the sense of "ground or land". Geo- is thus a prefix for many words dealing in some way with the earth, including:

Uri or URI may refer to: