Open source refers to software whose source code is publicly accessible and may be freely inspected, changed and redistributed by anyone. Open-source projects are usually carried by an active community of developers who jointly fix bugs, develop new features and keep improving the code – a fundamental contrast to the classic, closed model of proprietary software.
Open-source licences at a glance
Whether and how open-source code may be reused is governed by the respective licence:
| Licence | Copyleft (derivative works must stay open) | Commercial use |
|---|---|---|
| MIT License | No | Unrestricted, including in proprietary software |
| Apache License 2.0 | No | Unrestricted, incl. patent protection clauses |
| GNU General Public License (GPL) | Yes | Permitted, but derivative works must also be GPL-licensed |
Which licence is the right one depends heavily on the project’s goal – maximum distribution speaks for permissive licences like MIT, permanently open source code for copyleft licences like the GPL.
Advantages of open-source software for companies
- Transparency and verifiability: the open source code can be checked for vulnerabilities and quality by independent developers, instead of having to blindly trust the manufacturer’s claims.
- No licence costs: the absence of classic licence fees considerably lowers the entry barrier, even if implementation and operation still mean effort.
- Flexibility and adaptability: the source code can be adapted exactly to your own requirements instead of staying within the limits of a proprietary standard solution.
- No vendor dependence: without vendor lock-in, control over data and further development stays with the company itself, not with a single provider.
Well-known examples of open-source software
For virtually every paid software solution there’s an open-source alternative. Well-known examples are Linux (operating system), Firefox (web browser), Android (mobile operating system, open-source as AOSP), Git (version control) as well as WordPress and TYPO3 as content management systems. At aceArt too, open source is no exception but the foundation of the bulk of our technology stack, from Hugo as static site generator to the frameworks with which we develop custom software.
The 2026 trend: open-source AI
Open source increasingly plays a central role in artificial intelligence too: open language models have developed from a niche option into a serious alternative to proprietary AI services. For companies valuing data control and GDPR compliance, open models are often the only option under which models can be run locally or on their own infrastructure, instead of transmitting data to an external cloud provider. Here too it shows: permissive licences like MIT and Apache 2.0 are considered particularly business-friendly because they allow commercial use without restrictions.
Conclusion
Open source left its niche of idealists behind years ago; today it is the technical foundation of most of the modern software landscape, from operating systems through content management systems to AI models. Whether an open-source solution, proprietary standard software or a custom in-house build is the right choice for your project is something we’ll gladly work out with you as part of our custom software development or simply get in touch and we’ll take a look together.