ARM templates are the JSON that Azure Resource Manager actually deploys (Bicep compiles to this). Even if you write Bicep day-to-day, you’ll read ARM JSON in existing repos and the portal’s “export template” feature.

The standard sections:

• parameters — inputs
• variables — computed values
• resources — what to deploy (the required part)
• outputs — returned values
• plus $schema and contentVersion

Deployments are idempotent, support modes (incremental vs complete), and can be validated with what-if before applying — just like Bicep.

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "storageName": { "type": "string" }
  },
  "resources": [{
    "type": "Microsoft.Storage/storageAccounts",
    "apiVersion": "2023-01-01",
    "name": "[parameters('storageName')]",
    "location": "[resourceGroup().location]",
    "sku": { "name": "Standard_LRS" },
    "kind": "StorageV2"
  }]
}

1. Name the required section of an ARM template.
2. Identify how a parameter is referenced inside a resource ([parameters('x')]).
3. Explain the difference between incremental and complete deployment modes.
4. Describe when you’d read ARM JSON rather than write Bicep.

• ↗ Microsoft — ARM template structure