Free software

software distributed under terms that allow users to freely run, study, change and distribute it and modified versions

software that is both free (as in freedom) and open-source

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Free Software Foundation document defining free (libre) software

CSPro, short for the Census and Survey Processing System, is a public domain and Open source data collection and processing software package developed by the U.S. Census Bureau and ICF International. Serpro S.A. was involved in past development. Funding for development comes primarily from the U.S. Agency for International Development. The main purpose of this software suite is to design applications for data collection, processing and tabulation.