Open source refers to software that’s made available for anyone to view, use, modify, and share — because its source code is open, not locked away.
The term comes from the world of software development. Traditionally, companies kept their code private (called “proprietary software”). But open source flips that idea: it invites developers around the world to contribute, improve, and collaborate freely. The movement exploded in the late 1990s, with projects like Linux, Apache, and later Firefox, WordPress, and VS Code.
For users, open source means freedom — no license fees, no black boxes, no vendor lock-in. For developers, it’s about community and learning. You can fork a project, build your own version, or submit improvements. Open source software powers most of the internet, from servers to browsers to the phone you’re reading this on.
There are different licenses (like MIT, GPL, or Apache) that outline what you can or can’t do with the code. But the spirit is the same: openness, transparency, and collaboration.
Want to dive in? Explore GitHub, the world’s biggest hub for open source projects.
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