Add PortworxVolume on the Volume Concepts Page under docs/concepts/storage/volumes.md.

docs/concepts/storage/volumes.md

@@ -79,6 +79,7 @@ Kubernetes supports several types of Volumes:
    * `azureDisk`
    * `vsphereVolume`
    * `Quobyte`
+   * `PortworxVolume`
    * `ScaleIO`
 
 We welcome additional contributions.
@@ -512,6 +513,38 @@ before you can use it__
 
 See the [Quobyte example](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/examples/volumes/quobyte) for more details.
 
+### PortworxVolume
+A `PortworxVolume` is an elastic block storage layer that runs hyperconverged with Kubernetes. Portworx fingerprints storage in a
+server, tiers based on capabilities, and aggregates capacity across multiple servers. Portworx runs in-guest in  virtual machines or on bare metal
+Linux nodes.
+
+A `PortworxVolume` can be dynamically created through Kubernetes or it can also be pre-provisioned and referenced inside a Kubernetes pod.
+Here is an example pod referencing a pre-provisioned PortworxVolume:
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: test-portworx-volume-pod
+spec:
+  containers:
+  - image: gcr.io/google_containers/test-webserver
+    name: test-container
+    volumeMounts:
+    - mountPath: /mnt
+      name: pxvol
+  volumes:
+  - name: pxvol
+    # This Portworx volume must already exist.
+    portworxVolume:
+      volumeID: "pxvol"
+      fsType: "<fs-type>"
+```
+
+__Important: Make sure you have an existing PortworxVolume with name `pxvol` before using it in the pod__
+
+More details and examples can be found [here](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/examples/volumes/portworx/README.md)
+
 ### ScaleIO
 ScaleIO is a software-based storage platform that can use existing hardware to create clusters of scalable 
 shared block networked storage.  The ScaleIO volume plugin allows deployed pods to access existing ScaleIO