Open source software
It is software with source code that is publicly available under a license that gives users the right to study, change, and distribute the software as they wish. The term was coined in 1998 when a group of individuals pushed for title that was less ambiguous than free software. They changed the emphasis from freedom to security, cost savings, transparency, and other pragmatic benefits. The term is more palatable for the corporate world, even though it refers largely to the same software. While the GPL isn’t the only supported license, it remains one of the most prominent. Like free software, open source software can be distributed for free, but it doesn’t have to be.
Free software, software libre, or libre software is computer software that gives users the freedom to run the software for any purpose as well as to study, modify, and distribute the original software and the adapted versions. The rights to study and modify free software imply unfettered access to its source code.