What is Cloud Computing?

We hear that the cloud simplifies, yet it makes things more complicated (at first). It saves us money, yet unusually high bills have surprised many IT leaders and executives. The cloud is flexible, agile, and nimble, yet many get locked into single providers with less than optimal architectures and with substantial migration costs to change. We also hear that the cloud is not as secure as our data center, even though this has been proven false time and again.

In many ways, cloud computing reflects human nature. Everyone believes their idea is best. People sometimes blindly follow their beliefs regardless of the data. No single cloud provider, cloud service, or cloud architecture is perfect. They all have things that we wish were different. They have rules to follow, and they all peddle the line of being the only way to the truth and the promised land.

The cloud is not an answer for everything. It is a tool in the toolbox that has a purpose. When used appropriately, it is an incredible addition. When used incorrectly it can be painful, expensive, and career altering. Let's sort out what it is and what it is not.

We cover the formal definition later, but in essence, cloud computing is a new business model for the consumption and provisioning of information technology software, infrastructures, and related services. Additionally, this chapter covers:

• Cloud computing history
• Cloud computing definition
• Essential characteristics of cloud computing
• Cloud service models
• Cloud deployment models
• Similar technology models
• Cloud washing