Geocoding
This is the one hard part about going open source geo.
- Yonder - Compare geocoding results from multiple providers.
- GeoPy - Python library has a Yahoo and some opensource options.
- https://github.com/straup/js-geocoder
- https://github.com/straup/js-geolocation
- https://github.com/straup/js-reversegeocoder
- Edina Unlock - Excels with historic places but also uses modern UK data, and global modern places via GeoNames.org and Natural Earth.
- OSM Nominatim - Used in OpenStreetMap, tied to OSM data.
- OSM Imposm.geocoder - Optimized for German addresses.
- MapQuest's version of Nominatim - Warning, assumes USA addresses.
- GeoCommons GeoCoder - an open-source Geocoder using open data mostly just for the US using Census geography files
- Gisgraphy - an open-source Geocoder using open data
###Not a batch geocoder, but useful:
- http://aaronland.info/iamhere/ - Decimal degrees, DDMMSS, geohash, and WOE ID place reverse geocode.
- Geonames Reverse Geocoder services list
###What's in a location?###
Image source: DC MAR