Geolocation in general is the practice of determining the physical, real world location of a person, device or subject matter using digital information processed through the Internet or other electronic means of communication.
A growing trend in geolocation is deriving the city, ZIP code or region from which a person is or has connected to the World Wide Web by using their device's IP address or that of a wireless access points, such as those offered by coffee houses.
Another form of geolocation involves utilizing the exact location featured in photo or video content based on longitude and latitude coordinates attached digitally to the media file manually or by GPS-enabled cameras.
Determining the nation of an Internet user based on his or her IP address is relatively simple and accurate (95%-99% percent) because a country name is required information when an IP range is allocated and IP registrars supply that information for free.
Determining the physical location down to a city or ZIP code, however, is more difficult and less accurate because there is no official source for the information, users sometimes share IP addresses and Internet service providers often base IP addresses in a city where the company is basing operations.
Accuracy rates on deriving a city from an IP address fluctuate between 50 and 80 percent, according to DNS Stuff, a Massachusetts-based DNS and networking tools firm.
Even when not accurate, though, geolocation can place users in a bordering or nearby city, which may be good enough for the entity seeking the information. This happens because a common method for geolocating a device is referencing its IP address against similar IP addresses with already known locations.
Commercial geolocation service providers are continually discovering and developing new ways to improve their information databases, and therefore their accuracy, such as purchasing or bartering IP location data from ISPs and or websites on which users enter a city or ZIP when registering or ordering products.