Open source software is software with source code that anyone can inspect, modify, and enhance. "Source code" is the part of software that most computer users don't ever see; it's the code computer programmers can manipulate to change how a piece of software—a "program" or "application"—works.

Open source software is code that is designed to be publicly accessible—anyone can see, modify, and distribute the code as they see fit.

Open source describes software where the source code is available for anyone to view, use, change, and then share. Making source code publicly available allows others to build on and learn from it, enabling broad collaboration from people around the world.

Generally, open source refers to a computer program in which the source code is available to the general public for use or modification from its original design. Code is released under the terms of a software license. Depending on the license terms, others may then download, modify, and publish their version (fork) back to the community.

In the programming world, open source is a generic term for Open Source Software (OSS). Open-source software is built on source code that's open to everyone to view, change, extend, and distribute.