Open source

Open source is about rights, not price. Most open-source software can be downloaded for free, but the defining feature is that the licence lets you see and modify the code and does not tie you to one vendor. WordPress, Firefox, React and most of the tools behind modern websites are open source.

It is easy to confuse open source with "free to do anything with". Each project has a licence with conditions, and some code is published openly under licences that restrict commercial use, which does not meet the usual definition of open source. In AI, an open-weight model shares a trained model's weights but not always everything needed to rebuild it.

How it works

The authors publish the code, usually in a public repository, together with a licence. Licences fall into two broad families. Permissive licences, such as MIT and Apache, let you use the code in almost any project, including closed commercial ones, as long as you keep the copyright notice. Copyleft licences, such as the GPL, which WordPress uses, require that if you distribute software built from the code, you share it under the same licence.

Projects are maintained by volunteers, companies or foundations. Anyone can report problems or propose changes, and maintainers decide what to accept. Large projects have regular releases and security teams; small ones may depend on one person in their spare time.

Free to download does not mean free to run. Someone still has to host the software, keep it updated, apply security fixes and support the people using it. With open source, that work is yours or your developer's, or you can pay a company that offers hosting and support for it.

Example

A small association moves its website from a paid proprietary builder to WordPress. It pays nothing for the software, owns all its content and can choose any host. When its developer moves on, another developer can pick up the site without needing permission from a vendor, and many firms and freelancers offer WordPress support.

The trade-off appears in upkeep. The association now has to keep WordPress, its theme and plugins updated, and it learns to check how actively a plugin is maintained before installing it. One plugin it relied on is abandoned by its single maintainer, and because the code is open, its developer is able to switch to a fork that others continued.

Why it matters for your business

Open source lowers licence costs and reduces lock-in: you can change hosts, developers and suppliers without losing your site. Widely used projects also benefit from many people finding and fixing problems. The costs move into maintenance, security updates and support, which have to be planned rather than assumed. Before relying on an open-source component, look at when it was last updated, how many people use it and whether there is a company or community behind it. For WordPress plugins, the plugin directory shows the last update, the number of active installations and the support forum, which together give a quick sense of whether anyone is still looking after it. A popular plugin updated recently is a far safer bet than an obscure one untouched for years.

Common mistakes

• Assuming open-source software needs no maintenance because it cost nothing to download.
• Installing small, abandoned projects that nobody will patch when a security issue is found.
• Ignoring licence terms and building a product in a way that breaks a copyleft licence.
• Treating any code visible online as open source when its licence may not allow reuse.

Questions people ask

Is open-source software safe to use?

Well-maintained open-source software is generally as safe as proprietary software, and often safer, because many people can inspect and fix the code. Risk comes from unmaintained projects and out-of-date installations. Check update activity and keep everything patched.

Is open source the same as free software?

They overlap heavily. Free software emphasises the user's freedom to run, study, change and share software; open source emphasises the practical benefits of shared code. Most licences qualify as both. Neither term means the software must cost nothing, although it usually does.

Can I use open-source code in a commercial website?

Usually yes. Permissive licences allow almost any use with attribution, and the GPL allows commercial websites too. Conditions mostly apply when you distribute software to others. If you are building a product to sell, have a developer check the licences of what you include.