OSS
FOSS stands for Free/Open Source Software, which is a general term for both free software and open source software. Free software refers to software that can be freely modified and distributed, while open source software refers to software that has its source code publicly available and can be freely distributed without any specific conditions or restrictions on commercial use or redistribution.
OSS is an abbreviation for Open Source Software, which specifically refers to software that has its source code publicly available and can be freely distributed. Unlike free software, the conditions for distribution and use may vary, allowing for different licensing forms such as commercial restrictions or redistribution prohibitions.
Free Software is not to be confused with free software in the sense of being free of charge. It refers to software that can be freely modified and distributed, providing users with the freedom to make changes and distribute the software as they wish.
If you want to learn more about investigating trends in OSS for web development, you can refer to the article titled How to Investigate Trends in OSS for Web Development - Qiita.
In the context of web development, Open source and OSS are often used interchangeably to refer to software that has its source code publicly available and can be freely distributed.