File format obsolescence

File format obsolescence occurs when files can no longer be opened with available software—because vendors discontinued products, codecs vanished, or documentation was lost. It is a central driver of Format migration and emulation strategies.

Examples

Word-processor formats from abandoned suites, obsolete video codecs, and encrypted containers without keys are recurring case studies in preservation teaching.

See also

• Digital preservation
• Bit rot
• Digital dark age

Sources

• Format registry and national-library risk assessments.
• Digital curation curricula.