Open Source Definition
The Open Source Definition is used by the Open Source Initiative to determine whether or not a software license can be considered open source.
The definition was based on the Debian Free Software Guidelines, written and adapted primarily by Bruce Perens. They are by no means definitive even as applied to software. Clause 3 is the primary legal difference between free software and open source software as such, free software is stricter in interpreting 3. Clauses 5 and 6 are not a condition of any major open content license regimes, which commonly do restrict types of uses and users; for instance, Creative Commons has open content licenses that explicitly forbid commercial use.
