Yes. It is a distributed operating system that operates at the scale of the datacenter across all of the machines and aggregates them into what looks like one giant computer. With the DCOS, developers and operators no longer focus on individual machines but build applications and services that span entire datacenters.
The DCOS has a distributed systems kernel with enterprise-grade security, based on Apache Mesos. It contains a set of core system services, including a distributed init system (Marathon), distributed cron (Chronos), service discovery (DNS), storage (HDFS), and others, all capable of launching containers at scale. It provides a user interface, including a command line for controlling the DCOS and visual tools for understanding how your datacenter is operating.
An ecosystem of datacenter services are readily available with the DCOS, including services such as Apache Spark, Apache Cassandra, Apache Kafka, Apache Hadoop, Apache YARN, Apache HDFS, and Google’s Kubernetes, supported by Mesosphere and third parties as native services.
In order to aid quickly building distributed applications and services that scale with built-in high availability and fault tolerance, the DCOS has an API and a software development kit (SDK).