What is the purpose of the terraform plan command?

The purpose of the terraform plan command is to show what actions Terraform will take without applying them. When you run this command, Terraform analyzes the current state of your infrastructure as well as the desired configuration defined in your Terraform files. It then generates an execution plan that details the changes that will be made to the infrastructure, including resources that will be created, updated, or destroyed.

This staging phase allows users to review the planned changes before any adjustments are actually made, thereby minimizing the risk of unintended alterations to the infrastructure. This capability is crucial for ensuring that the user understands the impact of their changes and can spot any potential errors or misconfigurations before they take effect.

While some commands serve other purposes—such as applying changes directly, validating configurations, or displaying summaries of resources—it's the terraform plan command that specifically focuses on providing a preview of upcoming modifications, helping practitioners manage infrastructure changes with greater confidence and control.