Merging Data to Create Custom Reports and Letters
Most Word users think of mail merge as a synonym for "form letters" or "junk mail." Although it's true that Word can churn out form letters and bulk mailings until the cows come home, the term mail merge only hints at what you can do with this capability.
At its most basic, a mail-merge operation consists of two parts—a database and a document—and the "merge" just brings the two together. The database can contain just about anything—names and addresses are the most common contents, of course, but you can also stuff the database with product names, court case citations, serial numbers, invoices, test scores, or anything else you can fit into a database record.
The document, too, can take just about any imaginable form—yes, the first thing you think of is likely to be a form letter, but you can also add fields from your database to an envelope, catalog, e-mail or fax message, telephone book, Web page, financial report, stock inventory, or time log. For that matter, the "document" could simply be a text file, enabling you to use a mail merge to create a new database from an old one.
Although Word doesn't have the extensive merging capabilities of a full-strength database manager such as Access, it's the best tool to choose when you need to produce a document or series of documents based on data in a reasonably clean list. On the other hand, if you need to manipulate data extensively, or your primary goal is to produce bare-bones printed reports, the tools in Access or Excel are more appropriate.
Word's mail-merge features come in handy in a variety of circumstances. When you're working with form letters going out to a mailing list, Word lets you
Sort and/or filter the incoming data, removing records according to field-level criteria you establish (for example, you could specify "Only include people in New York or New Jersey").
Print envelopes or mailing labels, with USPS Postnet postal bar codes. You can even interleave the form letters with envelopes—print an envelope, then its letter, then the next envelope and its letter, and so on—using an undocumented technique discussed under "Merge Envelopes" later in this chapter.
Force the merge process to pause at each record, to enable you to type in custom information. Use this technique if you're producing a holiday newsletter, for example, and you want to add some unique content for each recipient.
When you move beyond basic form letters, Word's mail-merge capabilities let you
Send similar, but customized, e-mail messages or faxes to a large number of people.
Create a product catalog, parts list, or price sheet from a list (or database) of individual products.
Create an organization membership roster or telephone book from a list (or database) of members.
Tip from 
Most Office users tend to think of mail merge as producing one page (or form letter) per data record, but Word isn't so constrained. As long as you tell Word that you want to create a "directory," it will place data records on a page until the page gets full, and then go on to the next page. Thus, if you have a data file for your coin collection, home inventory, paid checks, office carpool, VIP donors, or best-selling books, you can use Word's mail merge to create a professional-looking, well-formatted report. Just call it a directory.
Word contains extensive support for running mail merges, embodied in the Mail Merge Wizard (which looks just like a task pane). To get to it, click Tools, Letters and Mailings, Mail Merge Wizard. The wizard handles almost every merge problem you're likely to encounter (see Figure 20.1).
Figure 20.1. The Mail Merge Wizard—the first wizard Microsoft ever created—appears as a task pane.
Although the wizard has its share of idiosyncrasies, it makes perfect sense after you've learned how to use it.
Tip from 
The first few times you run a mail merge, keep a detailed log of the steps you take—especially problems you encounter with Word or your printer. Chances are good you'll hit similar problems when using mail-merge capabilities sometime in the future, and good notes can save you precious troubleshooting time.
Each of the major types of mail merge is a bit different—Letters, E-mail messages, Envelopes, Labels, and Directories—so we're going to deal with each one separately.