Much of the time when we create a digital file, it is created in a proprietary format (think Adobe Photoshop or Sony Vega project files). This makes their access unsure down the road due to the possible inability to convert files or view files on newer software. While nothing is certain, the preferred file formats for file types listed below have become standard enough to where digital preservationists feel comfortable accepting them.
| Type | Primary Preservation Format (Preferred) | Secondary Preservation Format (Acceptable) |
|---|---|---|
| Text-based or word processing | Original (ex: DOCX), RTF, TXT, XML | |
| Spreadsheet or structured data | Original (ex: XLSX)CSV, Tab-delimited, TXT, XML | |
| Presentations | Original (ex: PPTX) | |
| Still Images | TIFF (uncompressed) | JPG, DNG, PNG, JP2 |
| Graphics | TIFF | |
| Video | Motion JPEG 2000, AVI, MOV | M-PEG 4 (mp4) |
| Audio | WAV, Broadcast-WAV | mp3 |
| Websites and Social Media | WARC | ARC, individual files and content from sites |
| XML (email preservation format) | ||
| GIS | TIFF (image files) PDF (structured data) | Original files |
| CAD | Original files |