GData (Google Data Protocol) provides a simple protocol for reading and writing data on the Internet, designed by Google.
Gdata (Google Data Protocol) provides a simple protocol for reading and writing data on the Internet, designed by Google. GData combines common XML-based syndication formats (Atom and RSS) with a feed-publishing system based on the Atom Publishing Protocol, plus some extensions for handling queries. It relies on XML or JSON as a data format.
Most Google APIs today are not Google Data APIs. The Google Data APIs applies only to a few APIs, as described in the GData API Directory