Add docs

README.md

@@ -10,10 +10,41 @@ Docker 1.5+ required.
 
 ## Running
 
-KVM, VirtualBox, and VMware all supported.  Just boot from the `rancheros.iso`
+KVM, VirtualBox, and VMware all supported (Clouds and Vagrant coming soon).  Just
+boot from the `rancheros.iso` from the [releases](https://github.com/rancherlabs/os/releases) page.
+
+## Logging in
+
+Log in with rancher/rancher and use `sudo` to get root access.
+
+Once cloud-init integration is finished we will not need to hard code the
+password anymore.
+
+## Persisting State
+
+Create a partition with the label `RANCHER_STATE`, for example
+
+    mkfs.ext4 -L RANCHER_STATE /dev/sda
+
+## Configuring
+
+The entire state of RancherOS is controlled by a single configuration document.
+You can edit the configuration with the `rancherctl config` command.
 
 ## Commands
 
 `docker` -- Good old Docker, use that to run stuff.
 
-`system-docker` -- The docker instance running the system containers
+`system-docker` -- The docker instance running the system containers.  Must run as root
+
+`rancherctl` -- Control and configure RancherOS
+
+## How does this work
+
+Everything in RancherOS is a Docker container.  We accomplish this by launching two instances of
+Docker.  One is what we call the system Docker which runs as PID 1.  System Docker then launches
+a container that runs the user Docker.  We created this separation as is really seemed like a
+bad idea that if somebody did `docker rm -f $(docker ps -qa)` they would delete the entire OS.
+
+![How it works](https://raw.githubusercontent.com/rancherlabs/os/master/docs/rancheros.png "How it works")
+