“Volunteered geographic information” (VGI) is the term most widely used to describe a variety of user contributions on the participatory Geoweb. These contributions range from coordinate locations and geometries to categorical observations, attribute tags, numeric measurements, and content ratings, as well as complex narratives, photos, and videos. Although researchers are creating and studying Geoweb applications, different types of VGI, and the related phenomena of neogeography, citizen science, and crowd-sourcing, systematic characterizations of user-contributed local knowledge are scarce. In this paper, we propose criteria to distinguish types of user-generated data and contents, and relate these to types of Geoweb applications. The proposed classification provides a conceptual framework to examine the participatory Geoweb, facilitate the processing of user contributions, and identify possible gaps in the data/content types currently used. This approach could help improve the effectiveness of current Geoweb applications, and increase the uptake of the valuable geographic information they generate.