2. It's always free
To be considered open source, the source code needs be freely available. That free availability does not mean the application itself is inevitably free. There are actually many companies making money from their open-source projects. Often, the suppliers tend to attach the price to areas such as support or added features. They also tend to make a community version of their product, which is free.
When a company sells a community version, it's usually a stripped-down, bare-bones variant of the commercial, open-source product. A great example of this approach is Zimbra, a powerful email and collaboration tool that offers a free, open-source edition as well as editions that have price tags and more features and less access to source.
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