Government Information - United States: Open Data / Open Government

Official sites

Data.gov
The purpose of Data.gov is to increase public access to high value, machine readable datasets generated by the Executive Branch of the Federal Government. Access datasets, geo data catalog, new apps, maps, and visualizations.
White House Open Government Initiative
The U.S. open government site is currently unavailable. Link leads to the White House web site.
NASA Open Data
Freely available apps, tools and data for anyone to use

What is Open Government?

Open government is a philosophy that advocates transparency, public participation, and collaboration in governance. Advocates for open source government seek widespread use of open source ICT's (information and communication technologies) and the addition of open source content (documents and data) to government websites and government publications services.