Merge branch 'master' of https://github.com/MicrosoftDocs/azure-docs-pr into update-subscription

Author: eross-msft

includes/media/virtual-machines-managed-disks-overview/disk-types.png

@@ -26,6 +26,10 @@ Using managed disks, you can create up to 50,000 VM **disks** of a type in a sub
 
 Managed disks are integrated with availability sets to ensure that the disks of [VMs in an availability set](../articles/virtual-machines/windows/manage-availability.md#use-managed-disks-for-vms-in-an-availability-set) are sufficiently isolated from each other to avoid a single point of failure. Disks are automatically placed in different storage scale units (stamps). If a stamp fails due to hardware or software failure, only the VM instances with disks on those stamps fail. For example, let's say you have an application running on five VMs, and the VMs are in an Availability Set. The disks for those VMs won't all be stored in the same stamp, so if one stamp goes down, the other instances of the application continue to run.
 
+## Integration with Availability Zones
+
+Managed disks supports [Availability Zones](../articles/availability-zones/az-overview.md), which is a high-availability offering that protects your applications from datacenter failures. Availability Zones are unique physical locations within an Azure region. Each zone is made up of one or more datacenters equipped with independent power, cooling, and networking. To ensure resiliency, there’s a minimum of three separate zones in all enabled regions. With Availability Zones, Azure offers industry best 99.99% VM uptime SLA.
+
 ### Azure Backup support
 
 To protect against regional disasters, [Azure Backup](../articles/backup/backup-introduction-to-azure-backup.md) can be used to create a backup job with time-based backups and backup retention policies. This allows you to perform easy VM restorations at will. Currently Azure Backup supports disk sizes up to four tebibyte (TiB) disks. For more information, see [Using Azure Backup for VMs with managed disks](../articles/backup/backup-introduction-to-azure-backup.md#using-managed-disk-vms-with-azure-backup).
@@ -36,11 +40,15 @@ You can use [Azure role-based access control (RBAC)](../articles/role-based-acce
 
 ## Disk roles
 
-### Data disks
+There are three main disk roles in Azure: the data disk, the OS disk, and the temporary disk. These roles map to disks that are attached to your virtual machine.
+
+![Disk roles in action](media/virtual-machines-managed-disks-overview/disk-types.png)
+
+### Data disk
 
 A data disk is a managed disk that's attached to a virtual machine to store application data, or other data you need to keep. Data disks are registered as SCSI drives and are labeled with a letter that you choose. Each data disk has a maximum capacity of 32,767 gibibytes (GiB). The size of the virtual machine determines how many data disks you can attach to it and the type of storage you can use to host the disks.
 
-### OS disks
+### OS disk
 
 Every virtual machine has one attached operating system disk. That OS disk has a pre-installed OS, which was selected when the VM was created.