What is the default state file for Terraform?

The default state file for Terraform is named "terraform.tfstate." This file is crucial because it maintains the mapping between the resources defined in your Terraform configuration and the real-world infrastructure. Each time you apply changes to your infrastructure, Terraform updates this state file to reflect the current state of your resources.

The naming convention "terraform.tfstate" is designed to clearly indicate its purpose, ensuring users can easily recognize it as the state file for their Terraform project. This file generally resides in the same directory as your Terraform configuration files unless specified otherwise with a different backend configuration.

In contrast, the other options do not represent the default naming convention used by Terraform. "state.json," for example, doesn't align with Terraform's default since the state is not stored in a JSON format by default. Similarly, "terraform.state" and "main.tfstate" are not recognized names in Terraform's built-in functionality for managing state files. The established convention is essential for both operational clarity and effective collaboration across teams utilizing Terraform for infrastructure management.