This multifaceted database from Columbia University's Center for International Earth Science Information Network (CIESIN) offers best-available human census data in a newly revised, straightforward format. Designed "to facilitate the use of population data in interdisciplinary research," the Gridded Population of the World (GPW) database marks a breakthrough in data format (and therefore simplifies analyses) -- enabling researchers to incorporate human population distribution and density data into their efforts. The site contains numerous images of 1995 human population (at the global and continental scales), in addition to GPW data (including population estimates and densities for 1990 and 1995). Instructions for downloading data and images are provided online.