free content
creative work with few or no restrictions on how it may be used
license-free software
software made available without a specified license, but with the apparent intention of allowing unrestricted use
free video
video content that is free to use for any purpose, or licensed under a free and open license to such an effect, at least for distribution, and at most for modification and commercial usage
open knowledge
knowledge which may be acquired, interpreted and applied freely
free music
music in the public domain or under a free license
Natural Earth
public domain geographic data collection