Great question! There is now a triad of Open Science, Open Data, and Open Source. They're clearly all related, but there's something unique about each. I'm guessing Open Source is first and foremost about software; Open Data is mostly about data regardless of what it is used for (apps, science, journalism, teaching, etc.); Open Science seems to encompass some of Open Data and the use of open source software for analysis, but is also about publishing, workflows, research ethics, etc. I'm looking forward to seeing peoples' opinions.
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