license overgrowth 
The ___MASK41___ Foundation ( FSF ) is a 501 ( c )( 3 ) non - profit organization founded by Richard Stallman on 4 October 1985 to support the ___MASK41___ movement , which promotes the universal freedom to study , distribute , create , and modify computer software , with the organization ' s preference for software being distributed under copyleft (" share alike ") terms , such as with its own ___MASK73___ . The FSF was incorporated in Massachusetts , USA , where it is also based . Linux ( pronounced or , less frequently ) is a Unix - like computer operating system assembled under the model of free and open - source software development and distribution . The defining component of Linux is the Linux kernel , an operating system kernel first released on September 17 , 1991 by Linus Torvalds . The ___MASK41___ Foundation uses the name GNU / Linux to describe the operating system , which has led to some controversy . Overgrowth is an upcoming action video game under development by Wolfire Games . It was announced on September 17 , 2008 for Windows , OS X and Linux . The game plays as a 3D third - person action game , set in a pre - industrial world of anthropomorphic fighter rabbits , wolves , dogs , cats and rats . The game is designed by David Rosen . Free and open - source software ( FOSS ) is computer software that can be classified as both ___MASK41___ and open - source software . That is , anyone is freely licensed to use , copy , study , and change the software in any way , and the source code is openly shared so that people are encouraged to voluntarily improve the design of the software . This is in contrast to ___MASK39___ , where the software is under restrictive copyright and the source code is usually hidden from the users . Linus Benedict Torvalds ( born December 28 , 1969 ) is a Finnish software engineer who is the creator and , for a long time , principal developer , of the Linux kernel ; which became the kernel for operating systems such as the Linux operating system , Android and Chrome OS . He also created the distributed revision control system Git and the diving logging and planning software Subsurface . He was honored , along with Shinya Yamanaka , with the 2012 Millennium Technology Prize by the Technology Academy Finland " in recognition of his creation of a new ___MASK30___ operating system for computers leading to the widely used Linux kernel ". He is also the recipient of the 2014 IEEE Computer Society Computer Pioneer Award . Open - source software ( OSS ) is computer software with its source code made available with a license in which the ___MASK20___ holder provides the rights to study , change , and distribute the software to anyone and for any purpose . Open - source software may be developed in a collaborative public manner . According to scientists who studied it , open - source software is a prominent example of open collaboration . GNU is an operating system and an extensive collection of computer software . GNU is composed wholly of ___MASK41___ , most of which is licensed under the GNU Project ' s own GPL .