Terraform provisions infrastructure declaratively across any cloud. You write HCL describing the desired state; Terraform figures out the changes to get there. The core workflow:

• terraform init — download providers and set up the backend
• terraform plan — preview create/change/destroy actions
• terraform apply — make it so
• terraform destroy — tear it all down

Building blocks: providers (cloud plugins), resources (things to create), variables (inputs), outputs (results), and data sources (read existing infrastructure). It’s declarative and idempotent — re-running converges to the desired state.

variable "region" { default = "eu-west-1" }

provider "aws" {
  region = var.region
}

resource "aws_s3_bucket" "data" {
  bucket = "my-app-data-12345"
  tags   = { env = "dev" }
}

output "bucket_name" {
  value = aws_s3_bucket.data.bucket
}

terraform init
terraform plan
terraform apply

1. List the four main Terraform CLI commands and what each does.
2. Write a variable, use it in a provider, and add an output.
3. Explain why Terraform is described as declarative and idempotent.
4. Run a plan and identify a create vs a destroy action in the output.

• ↗ Terraform — Get Started