Cloud and cloud computing are terms used on computer services that are delivered via the internet. Storage, networking, servers, databases, software, analytics, and intelligence are examples of these computing services.
Even though it is called cloud the data and programs are actually not in the clouds, but in large data centers around the world. As they are accessed via the internet, we call it cloud. It is the opposite of keeping your data on local hard disks and run on local servers in your office.