Open means ‘free,’ as in ‘free speech.’ We are all entitled to it by fundamental right.
Open means accessible. We have “open access” to things like roads and libraries — these are public goods, and anyone is able to use them. Likewise for our computer technology: open data can be accessed and used not just in one system, but any capable system.
Open does NOT necessarily mean ‘anything goes.’ Books have to be returned to the library, and in good condition. Roads have speed limits. You can’t yell ‘fire’ in a crowded theater. Etc.
Open does NOT necessarily mean ‘free’ as in without cost. Some roads have tolls; all roads need to be maintained. For something to exist in an open state, a lot of energy and resources must go into keeping it so. Those resources must come from somewhere (and, in the case of resource directory data, we don’t assume they will automagically crowdsource themselves).
‘Open’ can mean many things, but at its core, ‘open data’ entails1:
Accessibility: open data is accessible as a “machine-readable” resource, meaning it can be ingested and displayed by computer programs, and presumably downloadable over the internet. (There can be reasonable reproduction costs associated with certain kinds of access to open data.)
Reuse and Redistribution: open data is provided under terms that permit reuse and redistribution, including the intermixing with other datasets (although open data can be licensed to prohibit changes or to require documentation of changes). There should be no discrimination against fields of endeavor or against persons or groups (although open data can be published with ‘dual licenses’ that specify different conditions for different uses).
Openness entails a state of possibility.
When it comes to public information, data becomes more valuable when more people use it. (Conversely, resource data is less valuable when fewer people use it.) When it’s easy to access and use resource data by any means, it becomes easier for more people to do more things with the data, and as more people do more things with the data, feedback on the quality of the data increases, data about the use of the data can be collected and analyzed — and the maintainers of the data become more critical to the entire ecosystem.
Open Referral’s core question is about how resource data can be sustainably maintained as an openly accessible public good.
1 This is a modified version of the Open Knowledge Foundation’s Open Data definition.