Imagine generating a personalized giving statement, a baptism certificate or a mail-merge letter straight from your Rock data, formatted and ready to send. That is exactly what merge documents do: they let you use Lava, Rock's templating language, to build formatted documents, not just web pages. Rock ships with two formats: HTML - Create an HTML file and drop in Lava the same way you do elsewhere in Rock. Great for anything you will view or print from the browser.Word - Embed Lava in a Word document for polished, print-ready results with very little effort. For example, a Word merge document can turn a family's giving records into a formatted year-end statement in seconds. The sample documents show a few finished results so you can picture what is possible. Next we'll look at how to manage and use merge documents, then how to create and format your own.