How to Use an ODM to Map Data Structures to Classes

MongoDB is open source. You can install it on your own machines if you want to. But it's distributed by default. If you want full redundancy, it's a pain to host yourself. So instead they ask us to host MongoDB for them. We can save some money on development environments and things like that. It sort of scales with you. And then, yeah, the other thing is it's hosting on the cloud provider of your choice.