Chapter One

Foundations

What Infrastructure as Code buys you, the idea Terraform rests on, and the daily loop of init, plan, and apply — plus where Terraform sits among the other tools it gets confused with.

7 topics

Terraform is a small idea surrounded by a large vocabulary. The idea is that you describe the infrastructure you want in text, and a tool makes reality match — creating what is missing, changing what drifted, and remembering what it built. Everything else is detail in service of that.

This chapter lays the groundwork. What Infrastructure as Code actually solves and why declarative beats scripting, where Terraform fits next to tools like Ansible and CloudFormation, how to install it, what a provider is, the init/plan/apply loop you will run thousands of times, and the shape of the HCL language. The rest of the course assumes these seven pages.

Topics in This Chapter

What Infrastructure as Code Is

Defining infrastructure in version-controlled text instead of clicking a console. Why declarative beats imperative, what idempotency means, and the layers IaC splits into.

What Terraform Is

The configuration / providers / state model, why Terraform is provider-agnostic, the BSL license change, and where OpenTofu fits.

Terraform vs Other IaC Tools

Provisioning versus configuration management versus orchestration. Where CloudFormation, Pulumi, and Ansible sit, and how Terraform and Ansible work together.

Installing Terraform and the CLI

Getting the binary, managing versions across a team, the command surface you use daily, and the CLI configuration worth setting once.

Providers and the Registry

The plugins that teach Terraform to talk to an API, how you declare them, and the Registry as the authoritative reference for every resource argument.

Your First Configuration

The end-to-end loop: write a config, init to download providers, plan to preview, apply to create, destroy to tear down — and what each step reads and writes.

HCL Syntax Basics

Blocks, arguments, types, and references. How Terraform merges files in a directory, why HCL has no imperative loops, and what terraform fmt standardizes.