Azure Virtual Machines (VMs) is one of the oldest and most used services in Azure. Azure VMs has witnessed considerable development over the years; as a result, you can now have an Azure VM on the most popular operating systems. At the time of writing, Azure VMs is supported by a variety of operating systems that include, but are not limited to, Windows, Linux, Unix, and FreeBSD.
Azure VMs follows the infrastructure as a service (IaaS) model, so when using it you will be responsible for managing and configuring everything within the VM. You will not be responsible for managing and configuring the underlying hardware layer, however.