There are many times when you want to use data in either Access or Excel for other purposes, including sending letters, drawing maps, creating PowerPoint presentations, and more. For the most part, you probably don't want to retype all of your data, and to the extent that you deal with a large volume of data, it probably isn't practical. Things like mail merge have been around for a long time, but this chapter focuses on automation of other applications. For example, a mail merge from Word creates all of the generated documents from the data source at the same time. In Example 9-1, you will see how to determine which letter to send based on information in a table and have the application process each one individually. The end user still ends up with your entire data set processed, but the approach is very different and more precise.
While there may be exceptions, in order to perform automation with another application you need an application object, and you generally need a second object referenced by the File Open menu command in the application that you are automating. In some cases, you need a third object, an active document (consider Excel, in which the Workbook is a container for Worksheets, while in Word, you simply open a document with File Open). There will be other application-specific objects, but as soon as you get an active reference to another application and some type of document, you can begin performing actions.