Word makes it easy for you to take a list of names and addresses and merge them with a form letter, an envelope template, or mailing labels. This enables you to quickly create items for mass mailings that appear to others to be customized for each person on the mailing list.
Although the Mail Merge Wizard walks you through the merge process, the entire procedure can be somewhat confusing. Two different documents are produced during the merge process: a main document and a data source. The main document is your form letter or mailing label template, and the data source is a Word document that provides the list of names and addresses that are inserted into the main document during the merge.