Infrastructure as Code (IaC) — Explained with Examples

In this tutorial, you'll learn about Infrastructure as Code (IaC). We cover key concepts, practical examples, and best practices to help you understand and apply this topic effectively.

Infrastructure as Code (IaC) is the practice of managing and provisioning computing infrastructure — servers, networks, databases — through declarative or procedural configuration files rather than manual setup or interactive tools.

Instead of SSH-ing into a server to install packages or clicking through a cloud console, you write code that defines the desired state of your infrastructure. This code is version-controlled, reviewed, tested, and applied automatically. Two major approaches exist: declarative (you specify what you want, the tool figures out how — Terraform, CloudFormation) and procedural (you specify how step-by-step — Ansible, Chef).

Real-world analogy. IaC is like a recipe for a dish. Instead of calling a chef each time and describing the steps verbally, you write a cookbook. Anyone (or any machine) can follow the exact same recipe and produce the same meal every time.

Example (Terraform):

resource "aws_instance" "web" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"

  tags = {
    Name = "WebServer"
  }
}

Related terms: CI/CD, Configuration Management, Immutable Infrastructure, GitOps, Containerization

Related tutorial: Terraform Basics