Free/Libre and Open Content

Free content, or free information, is any kind of functional work, artwork, or other creative content having no significant legal restriction relative to people's freedom to use, distribute copies, modify, and to distribute derived works of the content. It is distinct from open content in that it can be modified, whereas one might not have that ability with content that is simply "open" and not "free".

Free content encompasses all works in the public domain and also those copyrighted works whose licenses honor and uphold the freedoms mentioned above. Because copyright law in most countries by default grants copyright holders monopolistic control over their creations, copyrighted content must be explicitly declared free, usually by the referencing or inclusion of licensing statements from within the work.

Though a work which is in the public domain because its copyright has expired is considered free, it can become non-free again with all its derivatives becoming non-free or illegal, if the copyright law changes.