What is FOSS/FLOSS?

FOSS is Free Open source software. FLOSS is Free/Libre/Open-Source software. The term "free software" was coined by Richard Stallman in 1983. Free software is more of an ideology. Free software does not imply free of charge, rather it means software that is available to the user along with the source code, and that which they can modify and redistrinbute. For educators, an example is Moodle. The source code is available. It can be changed according to your requirement and used for your own purpose, all this without incurring a plagiarism penalty!!!
The free software community in India uses the term "Swatantra Software" for Open source software.
The Free Software movement is headed by the Free Software Foundation, a fund-raising organization for the GNU project. Ii is an attempt to guarantee certain rights for both users and developers. These freedoms include the freedom to run the program for any reason, to study and modify the source code, to redistribute the source, and to share any modifications you make.