Terraform Fundamentals

Terraform lets you describe infrastructure in configuration files. It then uses provider plugins to manage real objects through their APIs.

Those objects can include networks, compute instances, DNS records, and software services. The provider determines which object types Terraform can manage.

Terraform is declarative. You describe the result you want instead of scripting every API call in order.

Why Terraform exists

Infrastructure changes often span many objects with dependencies between them. Manual changes are difficult to review, repeat, and reproduce.

Terraform turns the intended infrastructure into a document that your team can store and review. Its planning step shows proposed actions before they run.

This approach helps you answer three practical questions:

• What infrastructure should exist?
• What differs from that configuration now?
• What actions would move the real system toward the configuration?

Terraform does not replace the platform APIs. Providers translate Terraform resource operations into calls to those APIs.

The three-part mental model

Think of Terraform as a comparison among three views.

Configuration states your intended resources and relationships. Files ending in .tf form one configuration in a working directory.