Cloud Computing Foundations

Cloud computing changes how organisations obtain computing resources. In this lesson, you will learn to:

• Explain cloud computing as renting resources over the internet rather than buying hardware
• Identify the five characteristics of a genuine cloud service
• Distinguish cloud services from on-premises and rented physical servers

This lesson starts at the foundation: what cloud computing provides and how to recognise it.

The simplest accurate definition is this: cloud computing means renting computing power, storage, and services over the internet from a provider, instead of buying and running your own hardware.

Think about how a business used to get a new application running. Someone specified a server, got a quote, waited weeks for delivery, found space in a rack, connected power and network, installed an operating system, and only then handed it to the development team. The company owned that machine. It also owned every consequence of owning it: the failed disks, the cooling, the electricity bill, and the fact that the capacity was fixed until someone signed off on buying more.

Cloud computing replaces that with a rental relationship. The provider owns enormous buildings full of machines. You sign in to a web console, ask for what you need, and it exists within minutes. You never see the hardware and never touch it. When you're finished with it, you release it and stop paying.

The mental shift that matters most here is from ownership to access. You aren't buying a computer. You're buying the use of computing, in the same way you buy electricity rather than buying a generator.

• Jessica: So when the finance pack says "cloud," what are we actually buying? A machine somewhere?
• Ryan: Not a machine you own. You're renting capacity in a provider's data centre, and you pay for the hours you actually use it.
• Jessica: And if we need three more of them next month?
• Ryan: You create them yourself in the console, in minutes. If you need them for two weeks, you shut them down after and the charge stops.
• Jessica: That's the part I couldn't square. We've always had to buy first and hope we sized it right.

Notice that Ryan never mentions a technology. Every point he makes is about how the resource is obtained, paid for, and given back.