This paper is a comprehensive overview of the current state of scientific (mainly biological) data publishing. It offers valuable recommendations and is a good source of links to relevant papers, projects and discussions. Its particular value will be in providing information to the many working scientists who are interested in going the open-data route, perhaps in opposition to the data-publishing policies of their employers, or of the agency or institution that has contracted their work. The current paper supplies reasons and frameworks for open-data publishing which those scientists can use to argue the case. Until now, I suspect that many such scientists have only had advice from colleagues, as in this imagined conversation: A - "I put all my data into Zenodo." B - "I'd like to do something like that, but I have to publish in the house journal, and the data are under copyright, I think; I'm not sure. And how does putting data into Zenodo get you publication kudos?" My only criticism of the present paper is that it does not argue forcefully enough for data archiving that is genuinely open, i.e. with data retrievable anonymously, without pre-registration and/or insistence on agreement to data-use terms. In addition to the repositories promoted in the article, there are many others which are nominally public but which are behind a registration or agreement wall. The use of such repositories should, in my view, be actively discouraged. If we cannot get data from them without surrendering personal details or agreeing to what amounts to protection of intellectual property, then their data are not open.