The web contains specialized repositories for datasets in many scientific domains: life sciences, earth sciences, material sciences, and more. Similarly, many governments maintain repositories of civic and government data. However, much of that structured data is not readily available to search engines, which must extract the data from HTML pages in order to provide search services to users. When webmasters provide structured markup, they enable search engines to “understand” this metadata, which in turn improves data discovery, leading scientists to the information they need for their work.
For example, consider this dataset that describes historical snow levels in the Northern Hemisphere. This page contains basic information about the data, like spatial coverage and units. Other pages on the site contain additional metadata: who produces the dataset, how to download it, and the license for using the data. With structured data markup, these pages can be more easily discovered by other scientists searching for climate data in that subject area.