Open Source

Open Source is an idea about how software should be distributed — freely, in both senses of that word. You may reasonably ask what an idea has to do with building websites. This much: the overwhelming majority of the world’s sites run on software written under exactly this idea, which is to say on software that is legally free and free of licensing complications.

There is more to it than “no charge”. What matters just as much to open source is that the source code is available, so that anyone can improve the program or make their own modified version of it.

The opposite of open source is proprietary software. The key difference is not only that proprietary programs cost money, but that their owners restrict what users may do with them — how they may be used, copied or modified.

The idea has a legal form in the shape of free licences, of which the best known and most used is the GPL.

For site owners and for the people who build their sites, the practical value is licence cleanliness. You can be at ease about royalties (there are none) and about whether you are entitled to use the software (you are).

Software under open licences runs not only most of the servers on the internet, but every one of the popular content management systems, along with a great many of the tools developers work with day to day.

The largest technology companies support the movement and contribute substantially to it. Google maintains a dedicated portal for its open source work at opensource.google.

Governments do too. The United States National Security Agency publishes its own code at code.nsa.gov, offering it for any use including commercial, and says so plainly: the government benefits from having its technology improved by the open source community.