A common concern with resources provisioned in Azure is that the ease with which they can be deleted. A careless administrator can accidentally erase months of work with a few wrong clicks. Azure Resource manager locks can help here. Resource Manager Locks can allow organizations to put a predefined structure in place that prevents the accidental deletion of resources in their Azure Environment. Resource Manager locks can be associated with a subscription, resource group, or resource. Locks are inherited by child resources.
Resource manager Locks can be applied by going to specific blade for example resource, resource group, or subscription and selecting the Lock option in the blade.

There are two varieties of Locks.
- Read-Only locks, which prevent any changes to the resource.
- Delete locks, which prevent deletion.
Please note that Only Owner and User Access Administrator roles can create or delete management locks.