DataStoreinterface of the Data Store API represents a retrieved set of data, and includes standard properties for accessing the store's name, owner, etc., methods for reading, modifying and syncing data, and the
onchangeevent handler for reacting to changes to the data.
DataStoreChangeEventinterface of the Data Store API represents the event related to a record changed in the data store, i.e. this is returned once a change is made and the change event is fired (see
DataStore.onchangefor the handler).