At the Open Knowledge Foundation we believe strongly that open data is best
served with open tools.CKAN is open source, free software. This means that you can use it without any license fees
but more importantly, when you choose CKAN for your catalog you are also
ensuring that you retain all rights to the data and metadata you enter, giving
you freedom to move it elsewhere or manipulate it with your own tools without restriction.
There are lots of different open source licenses (you can find them at
http://opensource.org) but CKAN is licensed specifically under the terms of the
Affero GNU GPL v3.0.
One of the strengths of the open source model is in the communities that form
around free software products. The CKAN community is no different, and is
arguably one of the strongest open data communities in the world. Together, the
CKAN community has a wealth of knowledge and expertise that other people using
the CKAN software can draw on. The Open Knowledge Foundation draw on and
contribute to this rich resource to help us drive CKAN product development.
See the public tickets at http://trac.ckan.org, read the developer
documentation at /documentation/ or join the community mailing
lists at http://lists.okfn.org/mailman/listinfo/ckan-discuss.