Gratis versus libre is the distinction between "for zero price" (gratis) and "freedom" (libre). Gratis appears in many English dictionaries, including the Oxford English Dictionary. However, libre does so less commonly, and no English adjective signifies "liberty" exclusively and as distinct from "at no monetary cost". This distinction is often important in dealing with laws concerning the use of information, such as copyright and patents. The terms are often used in the free software and open source communities, as well as the broader free culture movement, to categorize computer programs according to the licenses and legal restrictions that cover them. Both this expression and the term gratis are used to distinguish freeware (gratis software) from freedom (libre) software.

Richard Stallman summarised the difference in a slogan: "Think free as in free speech, not free beer."