---
title: About Calico
canonical_url: 'https://docs.projectcalico.org/v3.9/introduction/index'
---

{{site.prodname}} provides secure network connectivity for
containers and virtual machine workloads.

{{site.prodname}} creates and manages a flat layer 3 network,
assigning each workload a fully routable IP address.
Workloads can communicate without IP encapsulation
or network address translation for bare metal
performance, easier troubleshooting, and better
interoperability. In environments that require an
overlay, {{site.prodname}} uses IP-in-IP tunneling or can work
with other overlay networking such as flannel.

{{site.prodname}} also provides dynamic enforcement of network
security rules. Using {{site.prodname}}'s simple policy language,
you can achieve fine-grained control over communications
between containers, virtual machine workloads, and
bare metal host endpoints.

Proven in production at scale, {{site.prodname}} v3.0 features
integrations with Kubernetes and OpenShift.

> **Note**: For integrations with the OpenStack,
> Mesos, DC/OS, and Docker (libnetwork) orchestrators, use
> [Calico v2.6](/v2.6/introduction/). We plan
> to resume support for these orchestrators in a future
> v3.x release.
{: .alert .alert-info}

<a href="/{{page.version}}/getting-started/" class="btn btn-primary btn-lg">Get started</a>
