Data architecture began with simple storage devices. But soon the need to store lots of data and to access the data quickly caused these early devices to disappear. In their place came disk storage. With disk storage, data could be accessed directly. But the need for managing volumes of data surpassed that of disk storage. One day there appeared Big Data. And with Big Data came the ability to effectively store unlimited amounts of data. But as Big Data grew, the older day-to-day systems did not go away. There began to be a need for a rational way to interface legacy systems to Big Data.