Does Ember CLI Mirage store data in a database? or the posted data gets removed after refreshing the browser?

I am a newbie to ember and i am using ember cli mirage for servers side API. For example, i want to POST a movie to the movies route, it gets added to the existing one's present in fixtures and is listed in localhost-4200/movies. On refreshing the browser, the one's posted gets erased and the default one's remain. Is this the expected behavior ?? Won't the details remain the same after browser refresh or when i reload the next time?