Cloud computing is when you access computing services - such as servers, storage, networking, software - over the internet("the cloud") from a provider like Azure. For example, instead of storing personal documents and photos on your personal computer's hard drive, most people now store them online: that's cloud computing.

Cloud computing platforms, such as Azure, tend to be less expensive and more secure, reliable and flexible than on-premises servers. With the cloud, equipment downtime due to maintenance, theft or damage is almost non existent. You can scale your compute and storage resources-up or down- almost instantly when your needs change on Azure. Also, you typically only pay for the services you use, which provides a level of convenience and cost-control that's almost impossible to achieve with on-site infrastructure.