libre and its meaning
Libre. From wikipedia "Gratis versus libre is the distinction between two meanings of the English adjective "free"; namely, "for zero price" (gratis) and "with few or no restrictions" (libre). The ambiguity of "free" can cause issues where the distinction is important, as it often is in dealing with laws concerning the use of information, such as copyright and patents.
The terms are largely used to categorise intellectual property, particularly computer programs, according to the licenses and legal restrictions that cover them, in the free software and open source communities, as well as the broader free culture movement. For example, they are used to distinguish freeware (gratis software) from free software (libre software)."