Mail merge is a software operation describing the production of multiple documents from a single document form and a structured data source. The letter may be sent out to many "recipients" with small changes, such as a change of address or a change in the greeting line. Microsoft Word Mail Merge allows a user to send letters or documents to many people simultaneously; users simply create one document that contains the information that will be the same in each version, and then add placeholders for the information that will be unique to each version. Mail Merge process depends on which user use. This slide created with Microsoft Office 2007.