Google Geocoding

The Google Geocoding API is a webservice for the Google Maps API. The Geocoding API provides a direct way to access a geocoder via an HTTP request, though it must be used in conjunction with Google Maps. Additionally, the service allows you to perform the converse operation (turning coordinates into addresses); this process is known as "reverse geocoding." Also, you can choose to limit your search to certain bounded areas (Viewport Biasing) or regions (Region Biasing).