Mt. Data (pronounced “mount data”, like “Mount Everest”) is a tool to help people collect and store (mountains of) public data from a variety of sources.
A dataset is a collection of related data, usually a single table. Each dataset knows how to download updates to the data, how to transform fields names and values, and which fields are useful for de-duplication.
A store is a means of persisting acquired data. For example, a particular store might know how to talk to a database to save data collected by datasets as database tables.