FLOSS

FLOSS stands for Free/Libre/Open Source Software and is applied to any software that is free for the user to study, modify and redistribute to anyone and for any purpose.

The Libre part is added to emphasize that it is referring to freedom of action, not just free as in no cost. FOSS is sometimes used as a varient of FLOSS, leaving out the Libre part. The two terms are often used interchangably.