What is the main purpose of parameters in an Azure Resource Manager template?

In an Azure Resource Manager (ARM) template, parameters play a crucial role in making templates reusable and customizable for different deployment scenarios. The main purpose of parameters is to supply values at deployment time, allowing the user to input specific data that tailors the deployment to their requirements.

This feature is particularly beneficial because it enables the same template to be used across various environments or situations without needing to modify the template itself. For example, a user might have a single template for deploying a virtual machine but can adjust the location, admin username, and VM size by providing different parameter values at runtime.

Parameters enhance the flexibility of ARM templates, and they streamline deployments by allowing easy adjustments without altering the core structure of the template. This design approach promotes best practices such as modularity and maintainability in infrastructure as code.