Hopefully by now you've had a chance to play with "Lava", Rock's templating engine. To know Lava is to love Lava. Much of the time Lava is used to format many of the pages in Rock. But what if you wanted to use Lava to format documents? Well, that's exactly what merge documents do. Rock ships with two different merge document formats: Word and HTML. The HTML format is pretty simple—just create a new HTML file and embed Lava much like you do elsewhere in Rock. The Word format makes it super simple to achieve amazing results. Let's take a look at the output from a few sample documents to see what's possible. Let's look at how you manage and use merge docs. Then we'll dive deeper into how to create and format them.