A file with .fods extension is a type of OpenDocument Spreadsheet document format that stores data in rows and columns. The format is specified as part of ODF 1.2 specifications published and maintained by OASIS. FODS files cannot be opened with Excel, another Spreadsheet software application by Microsoft. FODS files can be saved as ODS using LibreOffice and can be converted to other formats such as XLS and XLSX.
FODS File Format
OpenDocument defines ZIP as well as XML standards for its supported file formats. The FODS file format is based on single XML document format, alos known as Flat XML or uncompressed XML file. The use of zipped format is more common than the XML based OpenDocument formats such as in ODS. The OpenDocument technical specifications do not list any of the single XML documents and further details of such documents is not available.