The DataStore is a central point to manage data lists that can be used throughout the application and may be loaded from external sources. A typical example is a list of all countries. Multiple forms will use this data in a field. Instead of asking from the administrators to define this list for every form over and over again (with all the possible data inconsistencies), we created this central point for common data. By using imports and exports from and to Excel, data updates are done in a smooth and fast way. The DataStore also centralizes all translations & mail templates.
By making use of external data sources, any database can be queried, making it very easy to re-use data from existing systems. Think about cost centers, configuration managers, security information that can easily be used in forms and stores.