Word processing document originally created by StarOffice Writer, the word processor included with StarOffice suite; based on the OpenDocument XML format and is compatible with Apache OpenOffice (formerly OpenOffice.org) Writer, the successor to StarOffice Writer.
Apache OpenOffice now uses .ODT files to save documents.
NOTE: StarOffice was originally developed by Sun Microsystems, who was acquired by Oracle. Star Office became Open Office, an Oracle commercial product. Open Office is the same product as the free Apache OpenOffice, except Open Office includes a technical support package.