What 'the cloud' actually is

The cloud is somebody else's computer, in somebody else's building, rented by the hour.

That is not a joke at the industry's expense — it is the whole idea, and holding it in your head will keep you out of trouble. When you 'launch a server in the cloud', a company like Amazon or Microsoft allocates you a slice of a real machine, in a real building, with real electricity and real cooling. You pay for that slice for as long as it exists, whether you are using it or not.

Why anybody bothers. Before this, a business that wanted a website bought a physical server. It cost money up front, took weeks to arrive, sat in a cupboard, and if the business grew twice as fast as expected somebody had to buy another one and wait again. If the business shrank, the server sat there anyway, bought and paid for.

Renting changes the shape of that problem. You can have a server in ninety seconds, and you can destroy it in ten. If you need ten more on Friday you have ten more on Friday. That flexibility is what people are buying.

What it does not change. The machine is still a machine. It still runs Linux, it still has an IP address, it still runs out of disk, and somebody still has to know why it stopped responding. Cloud did not remove the need to understand computers — it removed the need to own them. This is why the paid course starts with Linux and networking rather than with a cloud console: people who struggle with cloud are almost always struggling with the computer underneath it.

The three big providers. Amazon Web Services (AWS), Microsoft Azure and Google Cloud. In Pakistan you will meet AWS and Azure far more often than Google Cloud. They use different words for the same ideas, which is confusing at first and stops being confusing surprisingly quickly.