"Data centers are buildings that host servers, storage, power, networking and all of the hardware necessary to operate a cloud. When dealing with cloud providers you are essentially working with a virtual data center. The cloud provider manages the physical data center, spread across various locations around the world, and you as the customer are responsible for putting your data and applications into these data centers through API’s and tools that the cloud provider give to you. This eases the burden of having to operate a data center, and allows businesses to focus on business logic for their applications and how they want to storage customers data."
in other words
Where data on the internet lives.