The beauty of the Store object is in its many uses. So many objects, within the Ext JS library, can consume a Store as part of their configuration, automatically mapping data in many cases.
For example, the ComboBox object can take a Store, or any of its subclasses, as a data provider for its values:
var combo = new Ext.form.ComboBox({
store: states,
displayField: 'state',
valueField: 'abbreviation',
typeAhead: true,
mode: 'remote',
triggerAction: 'all',
emptyText: 'Select a state...',
selectOnFocus: true,
applyTo: 'stateCombo'
});
This ComboBox takes a Store object called states, and maps its state field to the display, while mapping the abbreviation field to its underlying selected value.