A data repository is an online collection of data. It makes data sets from research available tor use and further study. A data repository can focus on general collections of data from various subjects, or it can be discipline-specific with data from select subjects or areas of research. Like other types of collections, a data repository may limit the data in their collections to those from research done within their institution or organization (also known as institutional data repositories) or may accept data collections that fall with in their areas of emphasis.
Why post data in a repository? Many researchers deposit their data in repositories for preservation purposes. Doing this assures that the data will be saved, especially considering when research groups change their personnel (or research interests). Some publishers (e.g., Nature) or funders require the sharing of research data. Sharing data through repositories also have the same benefits as sharing articles and publications: the work is easily discoverable, resulting in more views, citations, and impact.
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Directories of Data Repositories