Office Open XML Document

File extension: .docx, .docm Developed by: Microsoft Type of format: Document file format MIME: application/vnd.-openxmlformats-officedocument.-wordprocessingml.-document
The Office Open XML file formats are a set of file formats that can be used to represent electronic office documents. There are formats for word processing documents, spreadsheets and presentations as well as specific formats for material such as mathematical formulae, graphics, bibliographies etc.