Open source and free software are two terms that are often confused. In this post, we’ll clearly explain what each one means and how they differ.
Open Source
Open source software is code that’s shared openly with the community. Anyone can view, audit, and often contribute to it. This transparency improves security, since malicious code is easier to detect, and also allows projects to grow faster with help from contributors.
Open source is more of a development model than a social movement. Developers can release their code under a license of their choice—free or paid. So, just because a project is open source doesn’t mean it’s free of charge.
When using open source software, it’s important to read the license. Some licenses allow personal use but restrict commercial distribution or modifications.
Free Software
Free software gives users specific freedoms: to run, study, change, improve, copy, and share the software. It might be free of cost—but the key idea is freedom, not price.
The word “free” in free software means freedom, not “free as in free beer.”
All free software is also open source, but not all open source software is truly free in this sense. For example, a free software project can’t be turned into a closed-source product. This is enforced by licenses like the GPL (GNU General Public License).
What is GPL?
The GNU General Public License (GPL) was created by Richard Stallman to protect user freedom. It ensures that software stays free and open for everyone.
GPL is based on four essential freedoms:
- The freedom to run the program for any purpose.
- The freedom to study how the program works and adapt it.
- The freedom to share copies of the software.
- The freedom to distribute your modified versions.
If a developer modifies and redistributes GPL-licensed software, they must also release their code under the same license. This ensures that all future versions remain free.
“Open source is a development methodology; free software is a social movement.”
– Richard Stallman
Open Source vs Free Software
| Feature | Open Source | Free Software |
|---|---|---|
| Main Focus | Practical benefits, collaboration | User freedom and ethical rights |
| Philosophy | Development model | Social movement |
| Access to Source Code | Yes | Yes |
| Modification Allowed | Yes (depends on license) | Yes (always allowed) |
| Can Be Proprietary Later | Sometimes (depends on license) | No (GPL prevents it) |
| Commercial Use | Often allowed (license-dependent) | Allowed, but must remain free |
| Example Licenses | MIT, Apache, BSD | GNU GPL, AGPL |
| Created/Promoted By | Open Source Initiative (OSI) | Free Software Foundation (FSF) |
Stay secure! 🛡️