Cloud computing is everywhere. You use it on a daily basis for personal use—we can explore this a little bit, but we will also discuss cloud computing on an enterprise level. By the end of this chapter, you'll be able to clearly explain the benefits of cloud computing and provide some real-life examples. Microsoft 365 is an example of cloud computing. But before we discuss all that, we should explain what cloud computing is first. 

The concept of cloud computing has been evolving over decades to help everyone, from daily, personal use cases to those of businesses.

Originally, you could think of cloud computing as the shared computer infrastructures on college campuses. Students and faculty would use dumb terminals to connect to a mainframe or minicomputer, and each user would share the resources of a large system. In today's terms, though, cloud computing refers to using internet-connected devices to consume services provided elsewhere, typically in some sort of shared environment.

A few years ago, you might have used portable USB devices or an external hard drive to store or back up your documents, pictures, or music files. That way, you have your files with you if you are carrying that physical device. Devices with large storage capacities or small physical devices generally cost significant amounts of money, but they have fallen in price over the years.

Now, you may use a cloud storage space such as a OneDrive account for documents, images, and other files. You may be using a certain amount of storage at no cost, and perhaps you have the ability to purchase more at a small price. Cloud capabilities allow you to eliminate the need for physical storage items such as hard drives. As long as you are connected to the internet, you are able to access your data.

Let's switch gears to the enterprise level and see how cloud computing fits there. Cloud computing allows users to access applications and data quickly and efficiently using a service provider's data storage space and computing power. When a service provider builds out a network of computing devices, storage, or applications, a customer can pay to use these resources instead of having to build an infrastructure of their own. You could say that it is like the customer renting these resources from the service provider. Microsoft Azure is an example of Infrastructure as a Service (IaaS), where customers can build entire computing environments using the service provider's hardware, software, network, and storage resources.

Once built, a user can access these resources from anywhere, using any supported internet-connected device. Cloud computing allows organizations to outsource operational tasks such as updating servers and maintaining storage to service providers.

Now that you have a solid idea of cloud computing, let's explore its benefits in the next section. Understanding the benefits of cloud computing will strengthen your core concepts for the exam and will help you answer MS-900 exam questions that may come up.