The document provides an overview of the basics of mail merge in Microsoft Word, including: 1) The main parts of a mail merge are the main document, data source, and optional header source. Fields in the main document are matched to records in the data source. 2) Completing a mail merge involves three steps - creating the main document, attaching the data source, and performing the merge. The merge can output to documents, printers, emails or labels. 3) Common issues like missing data sources or mismatched fields can cause errors. Checking fields and previewing the merge are recommended before final output.