The file you preserve should not always be the file you email, embed, or publish. There is no one-line answer here: it depends on evidence from the source, the specific properties named below, and the destination's real requirements.
Inspect signatures, MIME type, container structure, and the receiving application's documented support. Before anything else in “Archival formats and delivery formats serve different jobs,” weigh this observation: Masters favor fidelity, openness, and metadata retention.
Three findings that guide this choice
The core distinction
Masters favor fidelity, openness, and metadata retention.
The practical trade-off
Delivery copies favor predictable playback, fast transfer, and small size.
The verification test
Version names and checksums matter as much as the chosen extension.
A practical decision for this workflow
Store a documented master plus reproducible export settings for the delivery copy.
Use version names and checksums matter as much as the chosen extension. as the acceptance test on a representative source before committing an entire archive, publication, or delivery batch.
The file formats mistake to avoid here
Overwriting the only high-quality source with a heavily compressed web export.
That failure conflicts directly with the recommendation for “Archival formats and delivery formats serve different jobs”: Store a documented master plus reproducible export settings for the delivery copy.
Review checklist before delivery
- ✓The file signature agrees with the extension.
- ✓The receiving app supports the container and internal encoding.
- ✓Required metadata or embedded resources remain present.
- ✓A richer master is stored separately from the delivery copy.
For “Archival formats and delivery formats serve different jobs,” success means the chosen result passes these topic-specific checks - Not merely that a new file opens.