Computer Applications
Answer
OSS refers to Open Source Software whose source code is made available to the public, allowing anyone to view, modify, and distribute the code. However, OSS does not necessarily mean that the software is completely free of charge. It only means that the source code is available for others to access and modify.
FLOSS refers to Free Libre/Livre and Open Source Software. The term FLOSS is used to refer to a software which is both free software as well as open source software. In addition to being Open Source, FLOSS also emphasises that no charges are applicable to the user for using and distributing the software.