dotx A .dotx extension file is a document template file where the x stands for XML (eXtensible Markup Language). The DOTX template files are created using the Microsoft Word Processor. They can either be content templates or layout template to suit custom needs. A DOTX template includes information on the auto text, settings, layout of the document, toolbars and macros. There are some standard .dotx format templates provided by Microsoft but users have the option to create customized templates as per required specifications for business correspondence including envelopes, letters, newsletters, training material, forms, brochures, announcements as well as for legal documents that include contracts and agreements.
docx In an effort to create an open document standard, Microsoft in collaboration with ISO/IEC and Ecma, developed the Office Open XML standard in 2006. One of the filename extensions supported in this specification is the .docx extension, a text document filename extension. The .docx was introduced in Microsoft Office Word 2007 and has been supported ever since in later iterations. It has become the default filename extension for all text documents produced using Microsoft Office Word. Given the open source nature of the XML specification, more alternative document processing applications support read and write capabilities on documents saved with the .docx filename extension. This is in comparison to the .doc filename extension which is a proprietary asset owned by Microsoft.