Gaining technical proficiency with Azure, starting from scratch, can be a daunting challenge. Azure has been growing at a fast pace, in both breadth and depth, since its inception - with documentation at the same scale. Not only do new features arrive frequently, but existing ones have changed and continue to do so. Finding your way through the very detailed documentation online can feel like working on a jigsaw puzzle without knowing in advance what the picture on the box is.
This introduction is designed to hit the Goldilocks point: fine-grained enough so as to give you the technical grounding you need, but not so much that you're getting lost in the weeds. The major concepts are presented in a logical order, covering all the prerequisites for working with linux virtual machines, with short hands-on examples that demonstrate the material, but callouts to the detailed docs if you want a deeper dive on that topic.
Azure is a remote distributed collection of virtualized resources, and the interfaces and tools that allow you to securely manage and interact with them.
Fundamentally, these interfaces are REST APIs - HTTP requests are made to initiate an operation, and the results are communicated back from Azure in the consequent HTTP response. While the REST APIs are great, they're not great for most humans to use directly, so various other abstractions have been built on top of them. There are SDKs and tools for various languages, such as Java, Node.js, and Python, and more importantly for our purposes here, two command-line interfaces: one in Powershell (now [open source and available for linux] (https://azure.microsoft.com/en-us/blog/powershell-is-open-sourced-and-is-available-on-linux/)), and a cross-platform (xplat) CLI written in Node.js. All of these ultimately communicate with Azure via REST, though.
Throughout this introduction, we will use the xplat CLI for the examples, so you'll want to have that [installed] (https://azure.microsoft.com/en-us/documentation/articles/xplat-cli-install/) before proceeding. We assume you have already been set up with a subscription (by your organization, or a free personal one) as well.
The example code in the sections that follow build on each other and are meant to be executed in the sequence below. If you skip around, you may run into errors from unmet dependencies. If that's your style, don't let that stop you! Figuring out why some example code doesn't work, and how to fix it, is a great way to learn. If you get stuck, though, you should be able to start over from the beginning with a clean slate and make it all work.