Workbooks often reference external resources, such as data sources, images, data files, or extract files. When you save a workbook to share with others, it's best to save a packaged workbook instead. Packaged workbooks are made of the workbook and the external resources. They are saved with the .twbx extension. Packaged workbooks can be viewed using a desktop, server, or reader.
To save a Tableau Packaged Workbook (TWBX), go to File | Save As. Provide a name for the the File name field and select Tableau Packaged Workbook:
