Congratulations on completing your first module! First, you learned that warehouse systems can exist onsite, on appliances, and on the cloud. You discovered that scalable data lakes enable organizations to provide fast, flexible data access, and serve as a self-serve staging area for machine learning development and advanced analytics, and that data marts provide specific, timely, and rapid support for making tactical decisions. You discovered that when selecting a data warehouse system, you need to consider the total cost of ownership, including infrastructure, compute and storage, data migration, and administration and data maintenance costs.