Azure Containers

Microsoft Azure has two container services:

Azure Container Service (generally available since April 2016 – you can also use Kubernetes as an orchestrator)
Azure Container Service - AKS (preview) - also known as container services (managed) is a dedicated managed Kubernetes service, in preview since Oct 2017 There are also the following services:
Container Groups (preview) - a top level resource for Azure Container instances. A container group is a collection of containers that get scheduled on the same host machine. They share a lifecycle, local network and storage volumes.
Container Registries - a private docker registry to store and manage container images.
Container Instances (preview) - a service for easily running containers without needing to worry about orchestration. I think this service is aimed at testing/development.

Azure Container Service

Available in all regions
The master Kubernetes machines are exposed to you in the Azure portal and are yours to manage (and pay for).

Kubernetes as a service. Currently in preview
Only available in the East US and Central US regions
The master Kubernetes machines are a managed service grouped and referred to as the “Hosted Control Plane”. You still control if/when Kubernetes version is upgraded (which can be done without downtime) but you aren’t having to otherwise pay for or manage the management machines.
Only pay for the virtual machines instances, storage and networking resources consumed by your Kubernetes cluster.
Azure Container Service is a free service, therefore it does not have a financially backed SLA. However, for the availability of underlying virtual machines, the Virtual Machine SLA applies.