> For the complete documentation index, see [llms.txt](https://bcds.gitbook.io/handbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bcds.gitbook.io/handbook/digital-pedagogy/maintenance-archiving/file-types.md).

# Recommended File Formats

The following file formats are recommended for maintaining and preserving digital content. They were taken from the Smithsonian’s [“Recommended Preservation Formats for Electronic Records.” ](https://siarchives.si.edu/what-we-do/digital-curation/recommended-preservation-formats-electronic-records)<br>

| **Type**                                                  | **Primary Preservation Format (preferred)**                              | **Secondary Preservation Format (acceptable)** |
| --------------------------------------------------------- | ------------------------------------------------------------------------ | ---------------------------------------------- |
| Text/word processing applications                         | PDF/A, PDF                                                               | RTF (text), TXT, XML with schema               |
| <p>Spreadsheet applications </p><p>or structured data</p> | <p>PDF/A (must capture entire workbook – macros disabled) </p><p>PDF</p> | <p>CSV</p><p>Tab-delimited</p><p>TXT, XML</p>  |
| Presentations                                             | PDF/A, PDF                                                               | Original                                       |
| Images                                                    | TIFF (uncompressed)                                                      | JPG, DNG, PNG, JP2                             |
| Graphics                                                  | TIFF                                                                     | PDF                                            |
| Video                                                     | Motion JPEG 2000, MOV, AVI                                               | MPEG-4                                         |
| Audio                                                     | BWF-Broadcast WAV (.wav is the extension)                                | WAV, AIFF, FLAC                                |
| Database Management Systems (DBMS)                        | Keep original                                                            | XML with schema                                |
| CAD                                                       | PDF/A, PDF/E or PDF with original file                                   | Original                                       |