What You Can Rent in the Cloud

Open the website of any big cloud provider and you'll meet a wall of two hundred service names, each with its own logo and its own three-letter abbreviation. It looks like an alphabet soup designed to keep you out. It isn't. Almost everything on that list is a variation on just a handful of basic things you can rent.

The cloud, remember, means using computers in someone else's data center, reached over the internet. What you actually rent from it falls into a few big categories: compute, storage, databases, and the networking that connects them. Learn those four, and the giant menu stops being intimidating.

A hardware-store rental counter is the closest everyday version of this. You don't buy the whole store; you walk up and rent the one tool the job needs — a drill this week, a tile saw the next — and hand it back when you're done. The cloud is that counter for computing: you rent the specific piece you need, for as long as you need it, and stop paying when you return it. Hold onto that picture; the four categories below are just the main shelves at the counter.

Compute: Renting Servers to Run Your Code

Compute is the category for renting a server — a computer that runs all the time, waiting to do work. When a company wants to run its website's code, or crunch a pile of numbers, it rents compute: one server, or a hundred, started in minutes and switched off when the work is done.

This is the heart of the cloud, because it's where your program actually runs. Everything else tends to feed it: the code lives on a rented server, reads files from storage, and looks things up in a database. When the earlier topics said the cloud lets you "start in minutes, not months," compute is the part you're starting.

Storage: Space to Keep Files and Data

Storage is exactly what it sounds like — rented space to keep files. Photos a phone app uploads, the backups a business can't afford to lose, the videos a streaming site serves: all of it sits in cloud storage, and you pay roughly for how much space it takes up.

The point of renting storage rather than buying disks is that it stretches. You never run out and you never have to guess years ahead how much you'll need. Upload one file or ten million, and the bill grows in step. There's no shelf to fill and no new drive to install.

Databases: A Managed Home for Structured Data

A database, from Chapter 9, is the organized place an application keeps its structured data — the user accounts, the orders, the records that have to be found fast and kept exact. In the cloud you can rent a database that someone else runs for you.

That word "managed" is the whole offer. Running a database yourself means installing it, backing it up, patching it, and keeping it from falling over — a real job. Rent a managed database instead and the provider does all of that maintenance; you just store and query your data. It's the same database idea from Chapter 9, with the upkeep handed off.

Networking and the Hundreds of Services on Top

Networking is the category that wires the rest together — connecting your rented servers to each other, to your storage and databases, and out to the internet so real users can reach them, with security controlling who's allowed in. It's the plumbing that turns a pile of separate rentals into a working system.

So where do the other two hundred service names come from? Almost all of them are built on these four. A service for sending email, one for running code without managing a server, one for analyzing huge datasets — each is a more specialized, pre-packaged combination of compute, storage, databases, and networking. Once you can name the four basics, the long catalog reads as variations on a theme, not a foreign language.