What is Docs-as-Code?

As part of a side project I've been working on, I wrote an introductory post about the docs-as-code workflow.

Here's the introduction:

The Docs-as-Code (DaC) approach to writing documentation has been gaining popularity in the last few years. Although it's a relatively new term, people have been using DaC-style workflows for almost as long as computers have existed. They just didn't call it "Docs-as-Code." The fact that lots of people have now heard the term is a testament to how many more people (and companies) are using the DaC workflow.